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SCIENCE
Class X
One Paper 3 Hrs.
Time : 2½ hours
Marks : 60
Unit
Marks
I
Chemical Substances
18
II
World of living
16
III
Effects of current
10
IV
Light
08
V
Natural Resources
08
Total
1.
60
Scheme of Question Paper
S. No. Type of Question
Marks for each
question
Total number of
questions
Total Marks
01.
Very short answer
01
09
09
02.
Short answer type I
02
09
18
03.
Short answer type II
03
06
18
04.
Short asnwer type III
05
03
15
27
60
Total
2.
Question paper will be divided into Sections A and B. No overall choice. Only internal
choice in all three questions of 5 marks.
3.
Estimated difficulty level of questions.
Easy : 15%
4.
5.
Average : 70%
Difficult : 15%
Type of questions :–
Knowledge based
40%
Understanding based
50%
Application based
10%
All the questions marked (*) are HOTS questions.
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X-Science (E.M.)
Chapter - 1
Chemical Reactions and Equations
Points to remember:1.
A chemical equation represents a chemical reaction occurring in a chemical change.
2.
A chemical equation is balanced so that the number of atoms of each element involved
in a chemical reaction are the same on the reactant and product sides of the equation.
3.
Combination reaction:- The reaction in which two or more substances combine to form
a new single substance.
4.
Decomposition reaction:- The reaction in which a single substance decomposes to give
two or more substances. It can be thermal (by heat) or electrolytic (by electric current)
decomposition.
5.
Displacement reaction:- The chemical reaction in which an element displaces another
element from its compound.
6.
Double displacement reaction:- The reaction in which two different atoms or group of
atoms (ions) are mutually exchanged.
7.
Precipitation reaction:- The reaction that produces insoluble salts.
8.
Oxidation is the gain of oxygen or loss of hydrogen.
9.
Reduction is the loss of oxygen or gain of hydrogen.
10.
Redox reaction:- The reaction in which one reactant gets oxidised while the other gets
reduced.
11.
Exothermic reaction:- Reaction in which heat is given out along with the products.
12.
Endothermic reaction:- Reaction in which energy is absorbed by the reactants.
13.
Corrosion:- When a metal is attacked by substances around it such as moisture, acids,
etc. it is said to corrode and this process is called corrosion.
14.
Rancidity:- When fats and oils are oxidised, they become rancid and their smell and
taste change.
QUESTIONS
1 mark questions:1.
What change do you observe, when magnesium ribbon is burnt in air?
2.
Define decomposition.
3.
Name the chemical reaction in which heat is absorbed.
4.
Name the type of reaction in which two or more substances combine to form a new
X-Science (E.M.)
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single product.
5.
What is Redox reaction?
6.
What happens when electric current is passed through acidified water?
7.
Define corrosion.
8.
Name one metal which does not corrode.
9.
Define Rancidity.
10.
Which type of chemical reaction takes place when Barium hydroxide and Ammonium
chloride, are mixed together in terms of heat released or absorbed?
11.
Name the type of reaction taking place when iron nails are dipped in copper sulphate
solution.
12.$ Name the group of chemical substances used to prevent oxidation.
13.$ Write one disadvantage of corrosion of metals.
14.$ Give one disadvantage of oxidation in our daily life?
2 marks questions:15.
What is balanced chemical equation? Why should a skeletal equation is to be balanced?
16.
What information regarding physical state do you get from the following notations – (g),
(l), (aq) and (s)?
17.
Arrange Iron, Zinc and Copper in increasing order of reactivity from the following reactions:Fe + CuSO 4 → FeSO 4 + Cu
Zn + FeSO 4 → ZnSO 4 + Fe
18.
Define combination reaction. Give one example of a combination reaction which is also
exothermic.
19.
When lead nitrate powder is heated. Mention the name and colour of the gas evolved?
20.
With the help of suitable example explain Oxidation and Reduction in terms of gain or
loss of oxygen.
21.
Write two methods by which oxidation process of food can be slowed down at home.
22.
What happens when a strip of zinc is dipped into a solution of copper sulphate? Write
the balanced chemical equation of the reaction.
23.
Translate the given statement, first in word equation and then into skeletal equation:Solutions of barium chloride and sodium sulphate in water reacts to give insoluble
barium sulphate and the solution of sodium chloride.
24.
Oil and fat containing food items (Chips) are flushed with Nitrogen. Give reason.
25.$ Respiration is considered an exothermic reaction. Explain why?
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X-Science (E.M.)
3 marks questions:26.
Define displacement reaction. Give one example of it. How is it different from double
displacement reaction.
27.
Define decomposition reactions. Give one example each of thermal decomposition and
electrolytic decomposition.
28.
For the following equation:Heat
Pb (NO3 ) 2 (s) 
→ PbO(s) + NO 2 (g) + O 2 (g)
(i) Write name and colour of the precipitate formed.
(ii) Balance the above chemical equation.
(iii) Name the type of chemical reaction.
29.
Write the balanced chemical equations for the following reactions:(i) Barium chloride + Potassium sulphate → Barium sulphate + Potassium chloride
(ii) Sodium chloride + Silver nitrate → Silver chloride + Sodium nitrate.
(iii) Calcium hydroxide + Carbon dioxide → Calcium carbonate + Water.
30.
Identify the substances that are oxidised and the substances that are reduced in the
following reactions:(i) ZnO + C → Zn + CO
(ii) CuO + H 2 → Cu + H 2O
(iii) MnO 2 + 4HCl → MnCl2 + 2H 2 O + Cl2
31.
Balance the following equations and state whether they are exothermic or endothermic:(i) Na + H 2 O → NaOH + H 2 + heat
Heat
(ii) FeSO4 (s) 

→ Fe2O3 (s) + SO2 (g) + SO3 (g)
Heat
(iii) CaCO 3 (s) 
→ CaO(s) + CO 2 (g)
32.
Name the type of chemical reaction represented by the following equations :–
Heat
(i) CaCO3 (s) 
→ CaO(s) + CO2 (g)
(ii) CaO(s) + H2O(l) → Ca(OH)2 (aq)
(iii) Zn(s) + CuSO4 (aq) → ZnSO4 (aq) + Cu(s)
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X-Science (E.M.)
5 marks questions:33.
Name the type of chemical reactions taking place when:(i) Lime stone is heated.
(ii) Magnesium ribbon is burnt in air.
(iii) Iron nails are dipped in copper sulphate solution.
(iv) Burning of coal.
(v) Sodium sulphate is mixed with barium chloride.
34.
Balance the following chemical reactions and state the type of chemical reactions:Electrolysis
(i) H 2 O 
→ H 2 + O2
(ii) CaO + H 2O → Ca(OH)2
Heat
(iii) CuO + H 2 
→ Cu + H 2 O
(iv) Pb + CuCl2 → PbCl2 + Cu
Heat
(v) FeSO 4 
→ Fe 2 O3 + SO 2 + SO3
35.
Translate the following statements into chemical equations and balance them :(i) Sodium chloride reacts with silver nitrate to give sodium nitrate and a precipitate of
silver chloride.
(ii) Hydrogen gas combines with nitrogen to form ammonia.
(iii) Zinc carbonate decomposes to give zinc oxide and carbon dioxide.
(vi) Ammonia gas reacts with water to give ammonium hydroxide.
(v) Copper (II) oxide on heating with hydrogen gas gives copper and water.
36.
In the reaction represented by the equation
NH 3 + O2 → NO + H 2O
Balance the equation and identify :–
(a) Substance oxidised
(b) the substance reduced
(c) the oxidising agent
(d) the reducing agent
37.
Name the types of reactions involved :–
(a) burning of Methane gas
(b) decomposition of vegetable matter into compost.
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X-Science (E.M.)
(c) Heating of Ferrous sulphate.
(d) exposure of silver bromide to sunlight
(e) Heating of copper powder in air.
38.$ (i) Write any two informations conveyed by a balanced chemical equation.
(ii) State the steps involved in balancing a chemical equation.
(iii) Sodium metal reacts with water to give sodium hydroxide and hydrogen.
Translate the statement into chemical equation and then balance.
(iv) Why are decomposition reactions called opposite of the combination reactions (any
one reason)
(v) Why magnesium ribbon is cleared before use?
39.$ Explain with suitable reasons :– (Write chemical equation also)
(a) Silver bromide is become kept in dark coloured (brown coloured bottles)
(b) Iron nails become brownish and then blue in colour when kept in copper sulphate
solution.
(c) Sodium sulphate reacts with barium chloride solution, a precipitation reaction takes
place.
(d) Calcium oxide reacts vigorously with water to form slaked lime.
(e) Carbohydrates broken down to form glucose combine with oxygen in cell provide
energy.
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X-Science (E.M.)
Chapter - 2
Acids, Bases and Salts
Points to remember:1.
Acid base indicators are dyes or mixtures of dyes which are used to indicate the presence
of the acids and bases.
2.
Acidic nature of a substance is due to formation of H + (aq) ions in solution.
3.
Basic nature of a substance is due to formation of OH – (aq) ions in solution.
4.
An acid reacts with a metal to form a corresponding salt and hydrogen gas is evolved.
5.
When an acid reacts with metal carbonate or metal hydrogencarbonate, it gives the
corresponding salt, carbondioxide gas and water.
6.
Acidic and basic solutions in water conduct electricity because they produce hydrogen
and hydroxide ions respectively.
7.
pH scale gives the measure of hydrogen ion concentration in a solution.
8.
pH of neutral solution is 7, while an acidic solution has a pH less than 7 and a basic
solution has a PH more than 7.
9.
Acids and bases neutralise each other to form corresponding salts and water.
10.
Mixing concentrated acids or bases with water is highly exothermic process.
11.
Water of crystallisation is the fixed number of water molecules chemically attached to
each formula unit of a salt in its crystalline form.
12.
Common salt, (sodium chloride), is a important raw material for various materials of daily
use, such as sodium hydroxide, baking soda, washing soda, bleaching powder, etc.
13.
Bleaching powder – CaOCl2
Chemical name : Calcium Oxychloride
14.
Baking soda – NaHCO3
Chemical name : Sodium hydrogen carbonate
15.
Washing soda – Na 2 CO3
Chemical name : Sodium carbonate
16.
Plaster of paris : CaSO 4 1 2 H 2 O
Chemical name : Calcium sulphate hemihydrate
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X-Science (E.M.)
QUESTIONS
1 mark questions:1.
Name two natural indicators.
2.
Name two synthetic indicators.
3.
What change in colour do you observe when methyl orange is mixed with an acid?
4.
What are those indicators called whose odour changes in acidic or basic media?
5.
Name two olfactory indicators.
6.
Name the gas evolved when dilute acid reacts with a metal.
7.
Define neutralisation reaction.
8.
Name the acid produced by our stomach.
9.
Name the group of substances, used to neutralise the excess acid in our stomach.
10.
Name the acid present in nettle leaves.
11.
Name the gas evolved when sodium hydroxide reacts with zinc.
12.
What will be the effect on pH on increasing hydronium ion concentration?
13.
Define dilution.
14.
Why Bee-sting causes pain and irritation?
15.
What are alkalis?
16.
While diluting an acid, why is it recommended that the acid should be added to water
and not water to the acid?
17.
Why acids do not show acidic behaviour in absence of water?
18.
Give reason:- Acids conduct electricity only in presence of water.
19.
How is the concentration of hydronium ion ( H 3O + ) affected when a solution of acid is
diluted?
20.
Name the components present in baking powder?
21.
Why is tartaric acid added to baking soda in baking powder?
22.
Write the chemical name of plaster of paris.
23.
What happens when the blue crystals of copper sulphate are heated?
24.
Fresh milk has a pH of 6. Write the change in pH when it turns into curd.
25.
Write the chemical formula of Plaster of Paris.
26.
Write the chemical name of milk of magnesia.
27.
Write the chemical name of bleaching powder.
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X-Science (E.M.)
28.
Which ion causes basic nature of substance?
29.
Three solution A, B, C have pH values 8, 9, 10 respectively. Arrange them in increasing
order of their basic nature.
30.
What is brine?
31.
Name the process involved in producing sodium hydroxide?
32.
What is gypsum?
33.
Write any two uses of washing soda.
2 marks questions:34.
Write the pH of following:(i) Gastric juice
(ii) Lemon juice
(iii) Blood
(iv) Milk of magnesia
35.
Four test tubes A, B, C and D contain the solutions having pH 3, 5, 8 and 12 respectively.
Arrange them in increasing order of acidic character.
36.
Write two differences between acidic and basic salts.
37.
Why does distilled water not conduct electricity, whereas rain water does?
38.
What is the effect of acid and base on phenolphthalein solution?
39.
What happens when metal carbonates and metal hydrogen carbonates react with acids?
Write the word equations for each.
40.
Define water of crystallisation. Write the number of water molecules present in one
formula unit of copper sulphate crystal.
41.
What will happen when sodium hydrogen carbonate is heated? Write the chemical
equation of the reaction involved.
42.
Under what soil condition do you think a farmer would treat the soil of his field with quick
lime (CaO) or slaked lime  Ca ( OH )2  ? What should be the nature of soil for a healthy
growth of plants?
43.
A milkman added a small amount of baking soda to fresh milk.
(i) Why does he shifted the pH of fresh milk to slightly alkaline?
(ii) Why does this milk take a longer time to set as curd?
44.
Define antacids. Give one example of antacids.
45.$ Name the chemical used in fire extinguisher and the gas evolved from fire extinguisher.
46.$ A baker found that the cake prepared by him is hard and small in size. Which ingredient
has he forgotten to add that would have made the cake fluffy? Give reason.
47.$ A metal compound X reacts with dilute Hydrochloric acid to produce effervescence. The
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X-Science (E.M.)
gas evolved extinguishes a burning candle and turns lime water milky. Identify the gas
evolved. Write a balanced chemical equation for the reaction if one of the compound
formed is CaCl2.
48.$ Give reason – HCl, HNO3, etc. show acidic characters in aqueous solutions while alcohol
and glucose solutions do not show acidic character?
49.$ Why plaster of paris should be stored in a moisture proof container? Write a chemical
equation of the reaction between plaster of paris and water.
3 marks questions:50.
Name the acid present in following natural sources:(i) Vinegar
(ii) Tomato
(iii) Tamarind
51.
Name the gas liberated when an acid reacts with a metal. Illustrate with an example.
How will you test the presence of this gas?
52.
Illustrate with an activity that compounds like Alcohol and Glucose contain hydrogen but
are not categorised as acids?
53.
Name the hardest chemical substance in the body, of which tooth enamel is made. At
what pH in the mouth it gets corroded? What kind of toothpaste should we use to protect
our teeth?
54.
Name the raw materials used in manufacturing of Baking soda. Write two important uses
of baking soda.
55.
Draw a flow chart showing uses of products from chlor-alkali process.
56.
A sanitary worker uses a white chemical having strong smell of chlorine gas to disinfect
the water tank. Identify the chemical compound. Write its chemical formula. Give the
chemical equation for its preparation.
57.
You are provided with three test tubes A, B and C. A contains distilled water, B and C
contains acidic and basic solutions respectively. If you are given only blue litmus paper,
how will you identify the nature of solutions in three tubes.
58.
On passing excess carbondioxide gas through lime water, it first turns milky and then
becomes colourless. Explain why? Write the chemical reactions taking place.
59.
Explain any three uses of plaster of Paris.
60.$ The pH of the mouth is lower then 5.5, what changes will occur in mouth? How these
changes can be controlled? Write any two measures.
5 marks questions:61.
Five test tubes A, B, C, D and E contain solutions having pH 2, 4, 14, 7 and 8 respectively.
Among these solutions which one is:(i) Strongly acidic.
(ii) Strongly basic.
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(iii) Neutral.
X-Science (E.M.)
(iv) Weakly acidic.
(v) Weakly basic.
Arrange the pH in decreasing order of hydrogen ion concentration.
62.
What is Chlor - alkali process? Write the chemical reaction taking place in form of
chemical equation. Name the gases given off at the anode and the cathode respectively.
Write one use each of any two products produced in this process.
63.
What happens when:(i) Excess of carbondioxide is passed through lime water.
(ii) Dry chlorine gas is passed over slaked lime.
(iii) Electricity is passed through an aqueous solution of sodium chloride.
(iv) Gypsum is heated at 373K.
(v) A solution of sodium hydrogen carbonate is heated.
64.
Out of sodium hydrogen carbonate, sodium carbonate, plaster of paris, bleaching powder,
sodium hydroxide.
(i) Name the compound used for setting fractured bones.
(ii) Name the compound used for making baking powder.
(iii) Name the compound used for softening hard water.
(iv) Name the compound used for bleaching cotton in textile industry.
(v) Name the compound used for making soaps and detergents.
Also write their chemical formula.
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X-Science (E.M.)
Chapter - 3
Metals and Non Metals
Points to remember:1.
Elements can be classified as metals and non-metals on the basis of their properties.
2.
Metals are lustrous, malleable, ductile, sonorous and are good conductors of heat and
electricity.
3.
Metals can form positive ions by losing electrons to non-metals.
4.
Metals combine with oxygen to form basic oxides while non-metals form acidic oxides.
5.
Aluminum oxide and Zinc oxide show the properties of both basic as well as acidic
oxides. These oxides are known as amphoteric oxides.
6.
Metals react with different reactivities with water to give hydroxides or oxides.
7.
Metals react with hydrochloric acid to form metal salt solution and hydrogen gas is
evolved.
8.
Order of reactivity of metals towards oxygen, water and acid is same i.e.
K>Na>Ca>Mg>Al>Zn>Fe>Pb>Cu>Ag>Au.
9.
Ionic bonds are formed by the transfer of electrons from a metal to a non-metal.
10.
Metals occur in nature as free elements or in the from of their compounds known as
minerals. Minerals from which metal can be profitably extracted are called ores.
11.
The process of extraction of metals from their ores and then refining them is called
metallurgy.
12.
The impurities like soil, sand, etc., present in ores are called. gangue.
13.
The surface of some metals, such as iron, is corroded when they are exposed to moist
air for a long period of time. This phenomenon is known as corrosion.
14.
Corrosion may be prevented by painting, greasing, galvanising, anodising or making
alloys.
15.
Galvanisation is a method of protecting steel and iron from rusting by coating them with
a thin layer of Zinc.
16.
An alloy is a homogeneous mixture of a metal with other metals or non-metal.
QUESTIONS
1 mark questions:1.
Name two most malleable metals.
2.
Name two metals which are best conductors of heat.
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X-Science (E.M.)
3.
Define Ductility. Name the most ductile metal.
4.
Name two metals which can be cut easily with a knife.
5.
Why are electric wires coated with P.V.C.?
6.
Which metals are said to be “SONOROUS”?
7.
Name one metal and one non-metal which exist in liquid state at room temperature.
8.
Name the non metal which is Lustrous and a metal which is non Lustrous.
9.
What is the nature of oxides formed by metals and non metals?
10.
Name the allotrope of carbon which is the hardest natural substance known and has a
high melting point.
11.
Name two metals which do not react with water?
12.
Why Sodium and Potassium metals are kept in kerosene?
13.
Select a most reactive and a least reactive metal from the following:Al, Ca, Zn, Fe, Hg, Cu
14.
Which two metals liberate hydrogen gas when react with dilute Nitric acid?
15.
What is the colour of flame when magnesium burns in air?
16.
What type of chemical bond is present in magnesium chloride?
17.
Name the process by which metals which are at the top of activity series are extracted
from their ore.
18.
Name one cheap reducing agent commonly used in extraction of pure metals.
19.
Define ores and gangue?
20.
Name the reducing agent in the following chemical equation :–
Fe2O3 + Al → Al2O3 + Fe
21.
In electrolytic refining, name the electrode which is made of impure metal and the electrode
which is made of pure metal.
22.
Name the electrolyte used in electrolytic refining of copper.
23.
What is an amalgam?
24.$ What is anode mud?
2 marks questions:25.
Explain Mg and Mn and most of the metals don’t react with HNO3. Give reasons.
26.
Explain why calcium metal after reacting with water starts floating on its surface. Write
the chemical equation of the reaction.
27.
Differentiate between Roasting and calcination. Give one example of each.
X-Science (E.M.)
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28.
A metal M left in moist air for a longer time, loses its shiny brown surface and gains a
great coat. What is this green coloured compound and identify the metal?
29.
Why ionic compounds have high melting point?
30.
Give reason:- Ionic compounds conduct electricity only in molten state not in solid state.
31.
An element A has atomic number 11 and another element B has atomic number 8. A and
B combine to form an ionic compound. What would be the formula of the compound
formed? Illustrate the formation of compound showing electron transfer.
32.
Define reactivity series of metals. Rearrange the following metals in increasing order of
their reactivity:Zn, Al, Fe, Cu, Au, Ca
33.
Why zinc oxide is called amphoteric oxide? Give one more example of amphoteric
oxide.
34.
An alloy is used in electronic industry to weld the components. Name the alloy and its
constituents.
35.
Illustrate the formation of bonds in:(i) Sodium chloride (ii) Magnesium chloride
36.
Write two methods of preventing iron from rusting.
37.$ Name two metals which melt if you keep them on the palm. Give reasons also.
38.$ Explain the use of aluminium as a reducing agent in metallurgy.
39.$ What is anodizing? For what purpose is it done?
3 marks questions:40.
What is meant by refining of metals? Name one method widely used for refining of
metals. How this method is different from electrolytic reduction?
41.
Write balanced chemical equations for the reaction taking place when:(i) Zinc carbonate is calcinated
(ii) Cinnabar is heated in air
(iii) Manganese dioxide is heated with aluminium powder.
42.
Define alloy and write the constituents of following alloys :–
(i) Stainless steel
(ii) Bronze
43.
What is the reaction between Iron (III) oxide and aluminium known as ? Write the chemical
equation. Write one use of this reaction.
44.
Write the chemical equations for the following reactions:(i) Iron reacts with steam. (ii) Calcium reacts with water.
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(iii) Copper is heated in air.
X-Science (E.M.)
45.
Give reasons for the following :–
(i) Metals are regarded as electropositive elements.
(ii) When a piece of copper metal is added to a solution of zinc sulphate, no change
takes place, but blue colour of copper sulphate fades when a piece of zinc is placed
in its solution.
46.
Write the systematic steps involved in the process of Extraction of a metal of medium
reactivity from its sulphide ore.
47.
Name the ore of Mercury. Name the method by which metals like mercury which are low
in the activity series can be extracted from its ore. Write the chemical reactions involved
in extraction of mercury from its ore.
48.$ Why some metals are reactive while some others are less reactive?
49.$ State which of the following chemical reactions will not take place, giving suitable reasons.
Zn( s) + CuSO4 (aq) → ZnSO4 (aq) + Cu ( s )
Fe( s) + ZnSO4 (aq) → FeSO4 (aq) + Zn( s)
Zn( s) + FeSO4 (aq) → ZnSO4 (aq) + Fe( s)
5 marks questions:50.
(i) What is corrosion of metals? Name one metal which does not corrode and one which
corrodes on being kept in atmosphere.
(ii) How will you show that rusting of iron need oxygen and moisture at the same time?
51.
A metal E is stored under kerosene. When a small piece of this metal is left open in the
air it starts warming up and the product formed is dissolved in water which turns the red
litmus blue:(i) Name the metal E.
(ii) Write the chemical equations for the reaction when it is exposed to air and when the
product is dissolved in water.
(iii) Explain the process by which the metal is obtained from its molten chloride.
52.$ A metal M which is one of the best conductor of heat and electricity is used in making
electric wires is found in nature as sulphide ore M2S.
(i) Name the metal M.
(ii) Which process will be suitable for extraction of this metal from its ore M2S?
(iii) Write the balanced chemical reactions involved in the process of extraction.
(iv) Draw a labelled diagram of electrolytic refining of the metal.
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X-Science (E.M.)
Chapter - 4
Carbon and its Compounds
Points to remember:1.
Carbon forms a large variety of compouds because of its tetravalency and the property
of catenation.
2.
Hydrocarbons are the compounds of carbon and hydrogen.
3.
Hydrocarbons are of two types – saturated hydrocarbons (alkanes) and unsaturated
hydrocarbons (alkenes and alkynes)
4.
Carbon forms covalent bonds with itself and other elements such as hydrogen, oxygen,
sulphur, nitrogen and chlorine.
5.
The functional groups such as alcohols, aldehydes, ketones and carboxylic acids bestow
characteristic properties to the carbon compounds that contain them.
6.
A group / series of hydrocarbons having similar structure and similar properties (i.e.
same functional group) is called a homologous series.
7.
Carbon chains may be in the form of straight chains, branched chains or rings.
8.
Carbon compounds with identical molecular formula but different structures are called
structural isomers.
9.
Saturated hydrocarbons on combustion give carbondioxide and water with lots of heat.
10.
Unsaturated hydrocarbons undergo addition reactions while saturated hydrocarbons
undergo substitution reactions.
11.
Ethanol and Ethanoic acid (glacial acetic acid) are carbon compounds of importance in
our daily lives.
12.
The molecules of soap are sodium or potassium salts of long chain carboxylic acids.
13.
Detergents are ammonium or sulphonate salts of long chain carboxylic acids.
14.
The action of soaps and detergents is based on the presence of both hydrophobic and
hydrophilic groups in the molecule and this helps to emulsify the oily dirt and hence its
removal.
QUESTIONS
1 mark questions:1.
Name the type of bond formed when sharing of electrons occurs.
2.
How many valence electrons are there in valence shell of carbon atom?
3.
Define catenation.
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X-Science (E.M.)
4.
What do you understand by unsaturated compounds?
5.
Why are unsaturated hydrocarbons more reactive than saturated hydrocarbons?
6.
What is the difference in number of carbon and hydrogen atoms between two successive
members of a homologous series?
7.
What is the difference in molecular masses of any two successive homologues?
8.
Name the functional group present in following compounds:(i) C2H5OH
9.
(ii) CH3COC2H5
Give the IUPAC name of the following compounds.
(a) CH 3 − CH 2 − Cl
H −C = O
(b)
H
10.
Substitution reactions are given by which type of hydrocarbons?
11.
Name the type of hydrocarbon taking part in an addition reaction.
12.
Name the products obtained from the complete combustion of saturated hydrocarbon.
13.
Acetic acid is also known as glacial acid. Why?
14.
Which gas evolved when sodium carbonate reacts with ethanoic acid?
15.
Name the catalyst commonly used in the process of conversion of vegetable oils into
fats.
16.
Write the colour of flame produced by unsaturated hydrocarbons on complete combustion.
17.
Which acid is regarded as dehyderating agent?
18.
What are hetro atoms? Give one example.
2 marks questions:19.
Draw electron dot structure of CH4 and O2.
20.
What is a homologous series? Write two main features of homologous series.
21.
Explain why saturated hydrocarbons give sooty flame on incomplete combustion?
22.
Differentiate between saturated and unsaturated hydrocarbons giving one example of
each.
23.
Which of the following hydrocarbons undergoes addition reactions & why :C2H6, C2H2, C3H8, C3H6
24.
Write the chemical formula and structural formula of:(i) Benzene
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X-Science (E.M.)
(ii) Propanoic acid
25.
Write names of following compounds as per nomenclature:(i) CH3CH2COOH
≡CH
(ii) CH3CH2C
26.
What are structural isomers? How many structural isomers can you draw from Pentane?
27.
What is hydrocarbon? Write the general formula of the hydrocarbons :(i) Alkane
(ii) Alkene
(iii) Alkyne
28.
What happens when a piece of sodium is dropped into a test tube containing ethanol?
Write the chemical equation also.
29.
A hydrocarbon compound A is active ingredient of wine and coughsyrups. A on oxidation
with acidified K2Cr2O7 forms compound B. Identify the compound A and B and write the
chemical equations involved.
30.
What is hydrogenation? Write its industrial application.
31.
Which type of reaction takes place when saturated hydrocarbons react with chlorine in
presence of sunlight? Write the chemical equation if the saturated hydrocarbon is methane
(CH4).
32.
What is scum? How is it formed?
33.
A, B and C are members of a homlogous series, there melting points are –1830 C,–1380 C
and –1300 C respectively. Among these:(i) Which member will have least number of carbon atoms?
(ii) Which member will have maximum number of carbon atoms?
34.
What are esters? How are they formed?
3 marks questions:35.
Write the chemical formula and structure of the following:(i) Cyclohexane
36.
(iii) Chlorobutane
Draw the electron dot structure of the following:(i) C2H6
37.
(ii) Propanal
(ii) C2H4
(iii) C2H2
Giving chemical equations of the reactions write what happens when:(i) Ethanol is heated at 443K with excess of concentrated sulphuric acid.
(ii) Conversion of oils (unsaturated hydrocarbon) into fats (saturated hydrocarbons)
(iii) Ethanoic acid reacts with sodium hydroxide.
38.
Draw 3 structural isomers butane.
39.
Explain formation of micelles with the help of suitable diagram?
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X-Science (E.M.)
40.
Explain the following terms with related chemical equations:(i) Dehydration
(ii) Esterification
(iii) Saponification
41.
Soap does not work effectively in hard water. Explain why?
42.
How can you obtain the following from pure ethanol :(i) Ethene
(ii) Ethanoic acid
(iii) Ester
Write the chemical equations of the reactions.
43.
Distinguish between addtion and substitution reactions with suitable examples.
44.
Differentiate between ethanol and ethanoic acid on basis of following test:(i) Blue litmus test
(ii) Reaction with sodium bicarbonate
(iii) Sodium metal test.
45.
Give reasons for the following observations :–
(i) The element carbon forms a very large number of compound.
(ii) Air holes of a gas burner have to be adjusted when the heated vessels get blackened
by the flame.
(iii) Use of synthetic detergents cause pollution of water.
46.
What is the difference between combustion and oxidation?
Under what condition an oxidation reaction can be cancelled as combustion? [Illustrate
your answer with one example each.]
5 marks questions:47.
Complete the following equation and write the names of product formed i.e. (A, B, C, D
& E)
Alkaline KMnO4
A
(i) CH3CH 2OH →
Heat
Hot conc H 2SO 4
(ii) CH 3CH 2 OH + A 
→ B + H2O
(iii) B + NaOH → C2 H 5OH + C
(iv) C + Na 2 CO3 ® CH 3COONa + D + H 2 O
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X-Science (E.M.)
(v) D + Ca(OH)2 → E + H 2O
white
ppt
48.
What are soaps? Explain the mechanism of the cleaning action of soaps? Soaps form
scum (insoluble substance) with hard water. Explain why? How this problem is overcome
by use of detergents?
49.
Give one example of each of the following :–
(a) A carbon compound containing two double bonds.
(b) A molecule in which central atom is linked to three, other atoms.
(c) A compound containing both ionic and covalant bonds.
(d) An organic compound which is soluble in water.
(e) A carbon compound which burns with a sooty flame.
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X-Science (E.M.)
Chapter - 5
Periodic Classification of Elements
Points to remember:1.
At present 114 elements are known to us.
2.
Elements are classified on the basis of similarities in their properties.
3.
Dobereiner grouped the elements into 'triads'. He showed that when the three elements
in a triad were written in the order of increasing atomic masses, the atomic mass of the
middle element was roughly the average of the atomic masses of the other two elements.
4.
J. Newland found that every eighth element had properties similar to that of the first and
it is known as Newlands Law of Octaves.
5.
A Russian chemist, Dmitri Ivanovich Mendeleev formulated a periodic law which states
that the properties of elements are the periodic function of their atomic masses.
6.
Mendeleev even predicted the existence of some yet to be discovered elements on the
basis of gaps in his periodic Table.
7.
Anomalies in the arrangement of elements based on increasing atomic mass could be
removed when the elements were arranged in order of increasing atomic number, a
fundamental property of the element discovered by Mosiley.
8.
Modern Periodic law states that the properties of element are periodic functions of their
atomic numbers.
9.
Elements in the Modern Periodic Table are arranged in 18 vertical columns called
groups and 7 horizontal rows called periods.
10.
Elements on left side of table are metals while elements on right side are nonmetals.
Elements between metals and non metals are metalloids.
11.
The valency of an element is determined by the number of valence electrons present in
the outermost shell of its atom. The valency of elements increases from one to four in
a period on going from left to right and then decreases to one and becomes zero in case
of inert gases. In a group all the elements have the same valency.
12.
The atomic size of elements decreases in moving from left to right along a period. In a
group atomic size increases from top to bottom.
13.
Metallic character decreases across a period and increases down a group.
14.
On moving from left to right in a period the electropositive character of element decreases,
but the electronegative character increases.
15.
Elements like boron, silicon, germanium, arsenic have intermediate properties of metals
and nonmetals and are called metalloids or semimetals.
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X-Science (E.M.)
QUESTIONS
1 mark questions:1.
What is the name given to group of three similar elements by Dobereiner?
2.
State "Newlands law of Octaves" for classification of elements.
3.
Name the fundamental property used by Mendeleev as the basis of classification.
4.
How many groups and periods are there in the Modern periodic table?
5.
What was the prediction of Mendeleev regarding the gaps in his periodic table?
6.
How is valency of an element determined?
7.
What will be the valency of an element having atomic number 16?
8.
How does valency vary in going down a group?
9.
Why inert gases have zero valency?
10.
What would be the valency of an atom containing 8 electrons in its outermost shell?
11.
How does the electronegative character of elements vary along a period of the periodic
table?
12.
The present classification of elements is based on which fundamental property of
elements?
13.
Among first ten elements in the modern periodic table name the metals present.
14.
Metals are on which side of Modern periodic table?
15.
State Mendleev’s periodic law.
16.
Name two elements, other than Gallium, whose existence was predicted by Mendeleev.
17.
State Modern Periodic law.
18.
Write the name given to the vertical columns in a periodic table.
19.
What name is given to the horizontal rows in a periodic table?
20.$ Why do silicon is classified as Metalloid?
2 marks question:21.
State two limitations of Newland's law of Octaves.
22.
Name the scientist who proposed modern periodic law? On which fundamental property
of elements it is based?
23.
Why could no fixed position be given to hyderogen in Mendleev’s Periodic table?
24.
What are metalloids? Give two examples.
25.
In group 1 of periodic table three elements X, Y and Z have atomic radii 133pm , 95pm
and 65pm respectively giving a reason, arrange them in the increasing order of their
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X-Science (E.M.)
atomic number in the group.
26.
In modern periodic table, the isotopes of Chlorine Cl-35 and Cl-37 having different
atomic masses will be kept in different slots or they would be assigned same position
on the basis of their chemical properties? Give reason in support of your answer.
27.
Nitrogen (At no. 7) and Phosphorus (At no. 15) belong to group 15 of the periodic table:(i) Write the electronic configuration of the two.
(ii) Predict whether they are metallic or nonmetallic in nature.
28.
How and why does the atomic size vary as you go down a group?
29.$ Why was Dobereiner’s system of classification of elements into triads not found to be
useful?
3 marks questions:30.
State three merits of Modern periodic table.
31.
What are amphoteric oxides? Choose the amphoteric oxide from among the following
oxides :–
Na2O, ZnO, Al2O3, CO2, H2O
32.
33.
Study the variation in the atomic radii of first group elements given below and arrange
them in increasing order :–
Group I element
Na
Li
Rb
Cs
K
Atomic Radii P.M
86
152
244
262
231
An element X has the electroic configuration as 2, 8, 7 :–
(a) What is the atomic number of the element?
(b) What will be the formula of its compound formed with Na?
(c) What is the name given to the family of this element?
34.
How do you calculate the valency of the element from its electronic configuration? What
is the valency of Mg with atomic number 12 and sulphur with atomic number 16? How
does the valency vary in going down in a group?
35.
Atomic radii of the elements of the period II are as follows :–
Period II elements :
Be
B
O
N
C
Li
Atomic Radius
111
88
66
74
77
152
:
(i) Arrange them in decreasing order of their atomic radii.
(ii) How does the atomic size vary on moving from left to right in a period? Explain why?
(iii) How will the tendency to lose electrons will vary on moving from left to right in this
period II?
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X-Science (E.M.)
36.
Oxygen (O, 8) and sulphur (S, 16) belong to group 16 of the periodic table :(i) Write the electronic configuration and valency of these two elements?
(ii) Which among these will be more electronegative? Why?
37.$ The positions of three elements A, B and C in the periodic table are given below:Group 16
Group 17
_____
_____
_____
A
_____
_____
B
C
(i) State element C is a metal or nonmetal.
(ii) Which is smaller B or C and why?
(iii) Which type of ion will be formed by A, B and C?
5 marks questions:38.
Two elements ‘A’ and ‘B’ belong to group 1 and 2 respectively in the same period.
Compare them with respect to :–
(a) Number of valence electrons.
(b) Valency
(c) Metallic character
(d) Size of atom
(e) Formulae of their oxides.
39.
From the table answer the following questions :–
1
2
Lithium
X
13
14
15
carbon
A
16
17
18
oxygen
L
Neon
S
G
Q
Y
R
Z
T
(a) Write the formulae of chloride of A.
(b) What is the electronic configuration of ‘S’?
(c) Name the noble gas.
(d) Write the formula of compound which carbon forms with G.
(e) What name is given to the family of group 17 element?
(423)
X-Science (E.M.)
Chapter - 6
Life Processes
Points to remember:1.
Movement of various types can be taken as an indication of life like running, breathing
etc.
2.
The maintenance of life requires processes like nutrition, respiration, transport and
excretion.
3.
Nutrition is of two types - Autotrophic and Heterotrophic.
4.
Green plants are considered as autotrophs while all other plants and animals as
heterotrophs.
5.
Heterotrophic nutrition involves the intake of complex material prepared by other
organisms.
6.
In Human beings food consumed is broken down by various steps along the alimentary
canal and the digested food is absorbed in the small intestine. Finally sent to all cells
in the body.
7.
Respiration may be aerobic or anaerobic. Aerobic respiration produces more energy to
organism.
8.
Vascular tissue which consists of xylem and phloem transports water. mineral, food and
other materials in highly differentiated plants.
9.
In human beings, the transport of minerals like oxygen, carbon dioxide, food and waste
is a function of circulatory system.
10.
In human being, excretory products are removed by nephrons in kidneys.
QUESTIONS
1 mark questions :1.
Name one basic element of food essential for all living organisms.
2.
Define Autotrophic nutrition.
3.
In most organisms the complex substances are taken as food from outside and then
broken down into simpler one by use of biocatalysts. What is this mode of nutrition
called?
4.
What are enzymes? Name an enzyme secreted by salivary glands.
5.
Name the movement occur all along the gut to move the food in the regulated manner.
6.
What is the name given to those cell organelle which contain green pigment? Name
green pigment also.
X-Science (E.M.)
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7.
Write down the chemical equation showing end products of photosynthesis.
8.
Name the enzyme responsible for changing starch to sugar in mouth.
9.
Name the part of digestive tract where complete digestion of carbohydrate, proteins and
fats occur.
10.
Name the muscles of stomach which regulate the release of food from stomach to small
intestine.
11.
Name the process by which energy is obtained by living organisms.
12.
Name the cells which regulate the opening and closing of stomata.
13.
Name the type of respiration in which no oxygen is needed from surrounding air.
14.
Name the intermediate 3 carbon molecule formed from six carbon molecules of glucose
during respiration.
15.
What is the site in cells where glucose is converted into 3 carbon molecule of pyruvate?
16.
Name the cell organelle where pyruvate breaks down, using oxygen.
17.
From where do the terrestrial animals get oxygen for respiration?
18.
How do hair help in nasal chamber?
19.
What is lymph?
20.
Name the air sacs in which bronchia terminate.
21.
Name the pigment present in blood of higher animals which supply oxygen to all tissues
for respiration.
22.
What products are formed during respiration in our muscles when there is less supply
of oxygen?
23.
Which component of blood prevents the loss of blood? Also name the process by which
it is prevented?
24.
What is the impact of leakage or loss of blood upon the pressure?
25.
Name the tissue which transport soluble products of photosynthesis in a plant.
26.$ What will happen to a plant if its xylem is removed?
27.$ Why rings of cartilage are present in trachea in throat region?
2 marks questions :28.
Only visible movement can not be used as the defining character for life. Give reasons.
29.
The molecular movements inside the body of living organisms helps them in survival.
How?
30.
What is the range of PH in small intestine and stomach respectively?
31.
Name the two glands associated with common duct. Also name their secretions.
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X-Science (E.M.)
32.
Write two important functions of transpiration in plants.
33.
Explain the statement, “Bile doesn’t contain any enzyme but its essential for digestion.
34.
Herbivores have a longer small intestine as compared to carnivores. Explain in brief.
35.
Respiration rate in animals is faster as compared to plants. Why?
36.
Which gas increases in blood and Alveoli after purification of blood?
37.
Arpit after a long walk suffers from muscular cramps. What can be possible reasons for
this observation? Name the process involved.
38.
What are two reasons for which plant has low energy needs?
39.
Give two main functions of HCl present in gastric juice.
40.
What do the following transport :–
41.
(i) xylem
(ii) pulmonary artery
(iii) pulmonary vein
(iv) vena cava
Why are the walls of ventricles thicker and more muscular then the walls of atria?
42.$ Write one feature which is common to each of the following pairs of terms.
(i) glycogen and starch
(ii) chlorophyll and haemoglobin
(iii) gills and lungs
(iv) arteries and veins
43.$ Select from the following organisms in which oxygeneted and deoxygenated blood mix.
Lizard, Pigeon, Dog, Whale, Frog, Dolphin, Snake
3 marks questions :44.
Compare the functioning of alveoli in the lungs and nephrons in kidneys with respect to
their structure and functioning.
45.
Write down the events occuring during the process of photosynthesis.
46.
Describe mode of nutrition in Amoeba with the help of a diagram.
47.
Describe the mode of nutrition in Amoeba with the help of diagram.
48.
Write the difference between Aerobic and Anaerobic respiration.
49.
Hari suggested Shashi that food in the stomach is not yet in the body. Do you endorse
Hari's view? Give reasons in support of your answer.
50.
Express the movement of sucrose in phloem.
51.
Enlist the various ways by which plants get rid of their waste products.
52.
Draw a labelled diagram of a transverse section of leaf.
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X-Science (E.M.)
5 marks questions :53.
Explicate the association between nutrition, respiration, transportation and excretion in
Multicellular organisms.
54.
Briefly mention the circulation of blood in human heart with the help of a labelled diagram
and write its significance.
55.
Describe the urine formation in human beings. Draw a neat and labelled diagram of
nephron.
56.
(a) Draw a diagram depicting human Alimentary canal, Gall Bladder, liver, Oesophagus
and pancreas.
(b) State the role of liver and pancreas.
(c) Name the organ which performs following functions in human :–
(i) Absorption of digested food
57.
(ii) Absorption of water
(a) Draw a sectional view of a human heart and label Aorta Pulmonary Artery and
Pulmonary Veins.
(b) State the functions of following components of transport system.
(i) Blood
(ii) Lymph
58.
Plants absorb water from a soil. How does this water reach the tree tops? Explain in
detail.
59.
(a) Draw a diagram of excretary system in human beings and label on it.
Aorta, Vena cava, Urinary bladder, urethera
(b) List two vital functions of the kidney.
60.
(i) Draw the diagram of heart and label its four chambers.
(ii) Construct a table to show the functions of these four chambers.
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X-Science (E.M.)
Chapter - 7
Control and Coordination
Points to remember:1.
All living organisms including plants and animals respond and react to environmental
factors or stimuli.
2.
Control and coordination are the functions of the nervous system and hormones in our
bodies.
3.
Response of nervous system:(i) Reflex actions
(ii) Voluntary actions
(iii) Involuntary actions
4.
Brain is divided into – Forebrain, Midbrain and Hindbrain.
5.
The nervous system receives information from sense organs and acts through our muscles.
6.
Chemical coordination is seen in both plants and animals.
7.
Plants show two different types of movements:(i) Dependent on growth
(ii) Independent of growth
8.
A feed back mechanism regulates the action of the hormones.
QUESTIONS
1 mark questions :1.
Name the most important organ related to control and coordinate our activities.
2.
Arrange the following sequence on the basis of their location from mid-brain : spinal
cord, pons and medulla.
3.
Ranveer rides a bicyle maintaining posture and body equilibrium. Identify the part of
brain which controls this acitivity.
4.
Which part of the brain is responsible for precision of voluntary action?
5.
What is the impact of nervous electrical impulse upon muscle proteins?
6.
What is synapse?
7.
Which part of brain is concerned with memory?
8.
Why blood pressure is considered to be an involuntary action?
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X-Science (E.M.)
9.
How is brain protected from shocks and injuries?
10.
Name any one movement of ours which occurs in order to protect ourselves.
11.
Name the part of brain in which hypothalamus is located.
12.
Gustatory and olfactory receptors related to which sensations?
13.
Define reflex action.
14.
Name the neuron that links motor and sensory neurons.
15.
Identify the system which facilitates the communication between the central nervous
system and other body parts.
16.
Write the components of Peripheral Nervous system.
17.
Name the place of origin of cranial nerves.
18.
Write the name of the thinking part of brain.
19.
Which two organs receive the information from all body parts and integrate it?
20.
Name two plant hormones that help in stem growth?
21.
Upon adrenalin movement along with blood stream, the blood supply to which two body
parts is reduced?
22.
What is the effect of adrenalin on the rate of beating of heart?
23.
How our growth is associated with thyroxin?
24.
Write the name of two hormones responsible for bodily changes in boys and girls around
the age of 10-12 years.
25.
Where is the adrenal gland in your body located?
26.
Which nutrient of food is associated with muscular action?
27.
Which of the two is slower - growth dependent or growth independent movement in
plants?
28.
Movement of which chemical compound help plants in changing shape?
29.
Where is auxin synthesized?
30.
What could be the possible disadvantage if reflex action were controlled by the brain?
31.
Which part of the brain would you associate with smell of delicious food?
32.$ Which organ secrets a hormone when blood sugar rises? Name one digestive enzyme
released by this organ.
33.$ Which hormone is responsible for
(i) phototrophic movement of plants
(ii) promoting cell division in plants
34.$ Defficiency in particular hormone in childhood leads to dwarfism. Name the hormone
and its source gland.
X-Science (E.M.)
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35.$ During conditions like fear and stress which hormones is secreted in aminals.
2 marks questions :36.
Enlist the functions of medulla.
37.
What does thinking tissue consist of? Where is it located?
38.
How is spinal cord related to the efficiency of reflex arc?
39.
What do you mean by chemotropism? Write its example also.
40.
A doctor advised a patient to take less sugar in her diet. Which disease is she suffering
from? Which body organ and connective tissue is related with it?
41.
Describe the feed back mechanism.
42.
What are the two limitations of electrical impulses?
43.
Enlist one advantage and one limitation of chemical communication.
44.
Draw a well labelled diagram of neuron (nerve cell)
45.
(a) label the two parts indicated by questions marks and label 1 and 2 in the above
diagram.
(b) Suggest a suitable heading for the above diagram.
46.$ Write the differences between Hormones and Enzymes?
47.$ What are ‘nastic’ and curvature movements? Give one example of each.
3 marks questions :48.
Draw a neat and well labelled diagram of human brain.
49.
Elucidate the nerve impulse mechanism.
50.
Write major functions of three parts of the brain.
51.
Write three differences between exocrine gland and endocrine gland.
52.
Elaborate the body's response to adrenalin secretion into the blood.
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X-Science (E.M.)
53.$ An element of halogen family is compulsorily added to common salt in small qunatity.
Identify the element. Also name the disease caused by its deficiency and write one
symptom of this disease.
54.$ Enlist the hormones secreted by ovary, testes and adrenal gland. Write one function of
each hormone.
55.$ How plants communicate the information of touch as stimulus as in touch-me-not plant?
56.$ Tendril encircles or coils around the object in contact with it. Elaborate.
5 marks questions :57.
Define plants hormones. Write the important functions of the following : auxin, abscisic
acid, gibberellin and cytokinin.
58.
Describe different tropic movements with suitable examples.
(431)
X-Science (E.M.)
Chapter - 8
How Do Organisms Reproduce
Points to remember:1.
Reproduction is essential for continuity of living organisms.
2.
It involves creation of a DNA copy along with the formation of additional cellular apparatus
during cell division.
3.
Basically it is of two types – Asexual and sexual. Some plants like Rose and Banana
are prolifrated by vagetative propogation.
4.
There are examples of asexual reproduction where new generation arises from a single
cell or single individual as in fission, fragmentation, regeneration, budding, spore formation.
5.
Sexual reproduction involves two individuals to produce off spring.
6.
Variation occurs due to DNA copying mechanism and sexual reproduction.
7.
Reproduction in flowering plants involve transfer of pollen grains from anther to stigma
– pollination. Gametes fertilize to form zygote.
8.
Changes occur in boys and girls at puberty, beard and moustache in boys and growth
in breast region in girls apart from other changes. These changes indicate sexual
maturation and biological preparedness for reproduction.
9.
Sexual reproduction takes place by fusion of both male and female gametes resulting in
the formation of zygote which gives rise to offspring.
10.
Awareness regarding family planning and sex related communicable diseases (STDs)
help individual to maintain normal reproductive health.
11.
Condoms, oral pills, copper T are some of the contraceptives to avoid pregnancy.
QUESTIONS
1 mark questions :1.
Why simply copying of DNA in a dividing cells not enough to maintain continuity of life?
2.
How does plasmodium undergo fission?
3.
How spirogyra reproduces by fragmentation?
4.
Which cells are responsible for budding in Hydra?
5.
On which plant can you find buds on its leaves?
6.
Write the scientific name of the bread mould.
7.
Name the structure into which following develops : the plumule and radicle?
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X-Science (E.M.)
8.
Where are the testes located in human beings?
9.
For what specific reason have the testes specific location?
10.
Correlate the rate of general body growth and maturation of reproductive tissue during
puberty?
11.
Where does the zygote get implanted?
12.
Which two important chemical substances are delivered to developing embryo through
placenta?
13.
Name the tissue in mother's body that provides nutrition to developing embryo?
14.
How change in hormonal balance prevents pregnancy?
15.
Write one side effect of loop placed in uterus?
16.
Which structures need to be blocked in males and females respectively to prevent
pregnancy?
17.
Write the ill effects of misuse of surgery?
18.
Why is children sex ratio alarmingly declining in our country?
19.
Name the chemical methods of preventing pregnancy.
20.
Name some of the devices used as mechanical method for preventing pregnancy.
21.
Expand AIDS?
22.
During spore formation in Rhizopus, which cells undergo reductional division?
23.
Which of the two has faster rate : asexual or sexual reproduction?
24.
Name the female reproductive part in center of flower?
25.
Write the names of area where buds are found in leaves of Broyphyllum?
26.
Identify the place in flower where zygote repeatedly divides forming embryo?
27.
In which structures of flower are ovules present?
28.
Name the two groups of living organisms which reproduce most commonly by fission.
29.
Name the cell organelle in which most of the amount of DNA is concentrated.
30.
Normally how many copies of DNA are fomed in a reproducing cell?
31.
From which part of the flower do following develop the fruit and the seed?
32.
Why reproduction is not referred as a life process?
33.
What is the role of DNA in reproduction?
34.
Name the structure so formed subsequent to fertilization of gametes.
35.
Is the age of puberty for both male and female the same in humans.
36.
Why is reproduction vital?
37.
Define niche.
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X-Science (E.M.)
38.
Name the structure which protect the spores.
39.
The two oviducts invite to form which structure.
40.
The slow down of the rate of general body growth marks the onset of which process?
41.
Write the function of mechanical barrier methods of construction.
42.
Why asexual mode of reproduction does not contribute to evolution?
43.
Why do the gametes have half the number of chromosomes than any other cell of the
body?
44.
Define contraception.
45.
Name one method which ensures population control.
2 marks questions :46.
Write two advantages of plants raised by vegetative propagation over those raised from
seeds?
47.
Enlist any four plants, which have lost capacity to produce seeds?
48.
Distinguish between asexual and sexual mode of reproduction.
49.
Why is greater degree of accuracy of DNA copying mechanism vital for survival?
50.
Compare unisexual flower with bisexual flower.
51.
Write two important functions of testosterone.
52.
Enlist the role of secretion of seminal vesicle and prostrate gland.
53.
Trace the path that a sperm cell undertakes before copulation.
54.
Describe the changes in lining of uterus in case the egg is not fertillized.
55.
Name two bacterial and two viral STD.
56.
Write the most common mode of reproduction in the following : Rhizopus, Hydra,
Paramoecium and Yeast.
57.
Draw a digram only to show multiple fission in plasmodium?
58.
Write the disadvantage of vegetative propagation?
59.
A newly born girl child, in her ovaries carries several immature eggs. Enlist the reasons
for the delay of process of biological maturation of these eggs?
60.
Sketch the diagram of Rhizopus showing spores?
61.
Name any two unisexual and any two bisexual flowers?
62.
Compare self-pollination with cross-pollination.
63.
Distinguish fragmentation from regeneration.
64.
Differentiate between binary and multiple fission.
(434)
X-Science (E.M.)
65.
How budding differs from spore formation?
66.
Distinguish male urethera from female urethera in humans.
67.
Distinguish a banana tree from a mango tree on the basis of mode of reproduction.
68.
How does the binary fission in Amoeba differ from that occurring in Leishmania?
69.
Name the parts of flower corresponding to the following present in animals.
(i) testis
70.
(ii) ovary
(iii) eggs
(iv) sperms
Why reproduction is considered a unique biological phenomenon?
3 marks questions :71.
How do the two germ cells differ from each other in complex living organisms?
72.
Onset the puberty involves certain common changes in boys and girls. Enlist them.
73.
Describe the role of variation for survival of species over period of time.
74.
Elaborate upon regeneration with the help of a diagram by citing suitable example.
75.
Differentiate between the germ cells of simple organisms and more complex organisms?
76.
Describe the reproduction through spore formation in Rhizopus.
77.
Enlist the bodily changes taking place during the early adolescence in boys and girls
respecitively.
78.
Draw a longitudinal section of a bisexual flower.
79.$ The consistency of DNA copying facilitates stability of population of any species.
Elaborate.
5 mark questions :80.
Describe the process of zygote formation in angiosperms with the help of a well-labelled
diagram.
81.
Explain the male reproductive structure in human beings with the help of a well-labelled
diagram.
82.
Describe the female reproductive system in human beings with the help of a welllabelled diagram.
83.
Define the following terms : fragmentation, binary fission, asexual reproduction, fertilization
and sexual reproduction.
(435)
X-Science (E.M.)
Chapter - 9
Heredity and Evolution
Point to remember:1.
Species maintain continuity by reproduction.
2.
Variation in different degrees occur.
3.
Variants have unequal chances of survival.
4.
In sexually reproducing individuals, for the same trait genes have two copies. Unidentical
copies bear dominant and recessive nature.
5.
Traits separately inherited, yields new combinations of traits in progeny.
6.
The sex of human progeny is determined by the sex chromosomes inherited from father.
7.
Variation in combination with geographical isolation might lead to speciation.
8.
Evolutionary relationship among living organisms become visible in hierarchy of
classification.
9.
Study of living forms as well as dead remains of organisms emerges as evolutionary
scene.
10.
DNA changes accumulated over a time span has resulted in evolution of complex organs
like eye as exhibited by structure of eye in different animals.
11.
Features like feathers have evolved as a function of change in allocated task.
12.
Evolution is not progress from lower to higher forms.
QUESTIONS
1 mark questions :1.
Which of the two exhibit greater variation : asexual or sexual reproduction?
2.
Why all the variants don't have equal chances of surviving?
3.
What is heredity?
4.
At which place on earth did humans appeared first?
5.
Give the name of plant studied by Mendel?
6.
Name the acid which is information source for making proteins in cells.
7.
What is the chemical nature of enzymes?
8.
Define gene.
9.
Which one of the two is shorter in length 'X' or 'Y'?
(436)
X-Science (E.M.)
10.
Determine the sex of progeny inheriting X chromosome from its father.
11.
Name any one place in India where Dinosaur's skull fossil was found.
12.
Name any one invertebrate fossil.
13.
Species A share ten characteristics with B, species C share fifteen characteristics with
D which of the two pairs share closer relation?
14.
Give an example of artificial selection from plants.
15.
Dead remains of two organisms A and B were buried. Later, only B's fossils were found,
but not A's. Give reasons.
16.
Write the possible range of pH of DNA.
17.
Green and red coloured seeds are recessive and dominant trait respectively. Out of F1
and F2 in which generation will the green seed appear.
18.
Give the term of the following : It is simply generation of diversity and shaping of
diversity by environmental selection.
19.
Identify the group of organism that can be found in places like hot springs, deep sea,
thermal vents and ice in Antarctica.
20.
Name any one fish fossil.
21.
Write the location of genes.
22.
With whcih branch of Biology would you associate John Mendal with?
23.
What is natural selection?
24.
Name the two factors which leads to the rise of a new species.
25.
Are human beings the pinnacle of evolution?
26.
Is evolution still occuring process?
27.
Write the basic characterstic of cell design in which cells differ from each other.
28.
Identify the following fossil and write the name of the family to which it belongs.
29.
Which method is extensively used to define evolutionary relationship?
(437)
X-Science (E.M.)
2 mark questions :30.
Name any four methods used for studying human evolution.
31.
Distinguish between dominant and recessive traits.
32.
Define a chromosome. What are the total number of chromosomes in sperm cells of
human males?
33.
Define acquired traits. Give examples.
34.
Describe the two ways of determining the age of fossils.
35.
XY and XX are sex chromosomes. Write the contribution of father and mother in each
of these sets.
36.
Define half way character. Give examples.
37.
Under what molecular conditions any trait is considered as recessive?
38.$ Evolution should not be equated with progress. Give reasons.
39.$ How can we say that bacteria has superior body design then a fish?
2 mark questions :40.
The reproductive cell undergo reductional division. Write the number of different types
of gametes produced from one XX and one XY. Also find the ratio of X to Y?
41.
Describe how the number of chromosomes is conserved in progenies?
42.
Explain how genes control traits?
43.
Enlist any three contrasting visible characteristices studied by Mendel in pea plant.
44.
In Mendel's experiment, F1 progeny had no halfway of intermediate features. Explain
this statement by giving suitable example.
45.
Explain possible way of evolution of eye.
46.
Give one example each of genetic drift and gene flow.
47.
Rahul and Parul were having a discussion on the superiority of complex over simple
body designs. You are asked to participate in the discussion and present your views.
48.
Prachi and Sumit were studying the homologous and analogous organs with the help of
wing of a butterfly, wings of a bat, forelimbs of horse and humans. You are asked to help
them providing reasons for your response.
49.
What is the evolutionary relationship between human beings and chimpanzee?
50.
Explain speciation.
51.
Trace the path of Y chromosomes received by a progeny since gamete formation in the
parent.
(438)
X-Science (E.M.)
52.
Tallness and wrinkled seeds are dominant traits against shortness and round seed.
Which feature (s) will be expressed in F1 and F2 respectively? Also write the different
pairs of the traits possible in this case in F2.
53.$ After their death, one of the insect was burried in hot mud and other is usually found
mud. Which of the two is more likely to be preserved better and why?
54.$ "A trail might be inherited but not expressed." Elaborate citing an example from Mendel's
experiments?
5 mark questions :55.
Design an experiment to show that traits are independently inherited?
56.
Differentiate between homologous and analogous organs. Give examples. Briefly describe
possible evolution of feathers.
57.
Write short notes on the following : evolution and fossils.
58.
Define the following terms : gene flow, hierarchy, characteristic, recessive traits and
genetic drift.
59.
With the help of a diagram explain the mode of sex determination in human beings.
Write any two inherited traits in human beings.
60.
Elobrate with an example how heirarchy of classification is related to characterstics.
61.
Two tall plants are crossed by a gardner. Tallness and dwarfness are dominent and
recessive traits respectively. It is possible for him to obtain both tall as well as dwarf
plant in F1 and F2 generation. Show with the help of the diagram of the cross(es).
(439)
X-Science (E.M.)
Chapter - 10
Light : Reflection and Refraction
Point to remember:1.
The phenomenon of coming back of incident light into same medium after striking the
surface of separation of two media is called reflection of light.
2.
There are two kinds of spherical mirrors:(a) Concave
3.
4.
(b) Convex
New Cartesian sign convention is used for spherical lens and mirrors.
The spherical mirror formula is
1 1 1
+ =
v u f
R
.
2
5.
The radius of curvature of a spherical mirror is half of its focal length i.e. f =
6.
The convex mirror always produce virtual image.
7.
Magnification by mirror =
8.
Negative magnification indicates real image whereas positive indicates virtual image.
(new Cartesian sign convention)
9.
The ray bends towards normal while traveling from rarer to denser medium & away from
normal when travels from denser to rarer.
10.
Speed of light is 3×108 m/s in vacuum, it is less in denser medium as compared to rarer
medium.
11.
Refractive index of medium =
12.
In glass slab the emergent ray is always parallel to the incident ray.
13.
The convex lens is called converging and concave as diverging lens.
14.
The lens formula is
15.
The reciprocal of focal length expressed in meters is called the power of lens
P=
height of an image h¢ – v
= =
height of an object h
u
Speed of light in vacuum / air
Speed of light in medium
1 1
1
– = .
v u
f
1
f(meters)
16.
SI units of Power of lens is diopter.
17.
The positive value of power indicates concave and negative value indicates convex
lens.
(440)
X-Science (E.M.)
QUESTIONS
1 mark questions :1.
Suggest a spherical mirror from which the image obtained is always Virtual and small?
2.
What is the type of mirror represented by inner shining surface of a spoon?
3.
The radius of curvature of a concave mirror is 3cm. Find its focal length.
4.
If an incident ray passes through centre of curvature of concave mirror, from where will
it pass after reflection?
5.
If the size of image obtained by spherical mirror is twice the size of an object, Identify
the kind of mirror.
6.
In which type of lens linear magnification is always less then one.
7.
Naseem obtained a magnification of 1 with concave mirror of focal length 10cm. What
is the object distance from mirror?
8.
Which mirror would give an enlarge size of your face when you view it from a close
distance?
9.
Which mirror has a wider field of view?
10.
Define refractive index of medium.
11.
How does speed of light change when it travels from optically rarer to denser medium?
12.
Which is optical denser out of the two mediums M1 and M2 having n = 1.71 and 1.36
respectively?
13.
Refractive index of Kerosene oil is 1.44 and that of water is 1.33. A ray of light enters
from kerosene oil to water. Where would light ray bent?
14.
Define magnification.
15.
Define 1 Diopter.
16.
Name the type of spherical lens where image formed is always small & erect.
17.
Identify a mirror having focal length – 15cm.
18.
Why does a ray change its path when it passes from one medium to another medium?
19.
When a ray of light entering from air is incident on a surface of a glass slab at an angle
of 90°, what will be the measure of angle of refraction?
20.$ Due to which property of light, sharp shadows of opaque objects are obtained?
21.$ What is the basic cause of refraction?
22.$ Where should be an object be placed in order to use a convex lens as a magnifying
glass?
(441)
X-Science (E.M.)
2 marks questions :23.
State laws of refraction.
24.
Two medium with refractive index 1.31 & 1.50 are given. In which case.
(i)
25.
Bending of light is more. (ii)
Speed of light is more.
Draw a path of light as it enters from:(i)
Air to glass.
(ii)
Glass to air.
26.
Why does the coin placed at the bottom of the container appears to be raised when the
container is filled slowly with water?
27.
The paper get burnt when a concave mirror was kept 15.3cm. away from it. Find the focal
length & radius of curvature of mirror?
28.
The lens has power of +2.5D. Find the focal length and nature of the lens.
29.
Why does a paper start burning when sun rays are reflected by a concve mirror as bright
sharp spot of light on it?
30.
Draw a ray diagram for image formation when the object is placed at F in front of
concave lens.
31.
When we hold a pencil in a upright position in front of the convex mirror. What is the
narture of the image formed? What will happen if we move the pencil slowly away from
the mirror?
32.
Why are convex mirror are preferred as rear view mirrors in vehicles?
33.
Give two applications of concave mirrors alongwith reasons.
34.
Under what circumstances there won’t be any refraction of light when it enters from one
medium to another?
35.$ Light travels through water with a speed of 2.25 x 108m/s. What is the referactive index
of water? (Given :– Speed of light in vacuum = 3 x 108m/s.)
36.$ In case of glass-slab, emergent ray is parallel to incident ray, explain.
3 marks questions :37.
Draw the ray diagram of image formed when an object is placed in front of convex lens
at:(i) Centre of curvature.
(ii) Between focus and optical centre.
38.
You are given a plane mirror, convex mirror and concave mirror. Without touching them,
how will you identify them?
39.
An object of 4cm. height is placed at a distance of 15cm. away from the convex lens
of focal length 10cm. Find the nature, size, position of the object. Find its magnification.
(442)
X-Science (E.M.)
40.$ Comment on the size, position of the image formed by a concave mirror of focal length
15cm when an object is placed:(i) At 20cm
(ii) 10cm
(iii) 35cm
in front of a mirror without calculation.
5 marks questions :–
41.
42.
(a)
State the relation between object distance, image distance and focal length of a
spherical mirror.
(b)
Draw a ray diagram to show the image formed by a concave mirror when an
object is placed between pole and focus.
What is the minimum number of rays required for locating the image formed by a concave
mirror for an object? For which position of an object a concave mirror gives same sized
inverted image. Show by drawing a ray diagram.
43.$ Draw and exaplain the ray diagram formed by a convex mirror when
(i) object is at infinity.
(ii) object is at finite distance from the mirror.
(443)
X-Science (E.M.)
Chapter - 11
Human Eye and the Colourful World
Points to remember:1.
The lens system of an eye comprises of cornea, aqueous humour, crystalline lens and
vitrous humour.
2.
Iris adjusts the size of the pupil.
3.
The capability of the eye to focus nearby as well as far-off objects an retina is called
power of accommodation.
4.
The least distance of distinct vision for normal eye is about 25cm.
5.
The common defects of vision are:(i) Myopia
(ii) Hypermetropia
(iii) Presbyopia
6.
The Myopia is corrected by using concave lens.
7.
The Hypermetropia is corrected by using convex lens.
8.
The prism split incident white light into band of seven colours.
9.
The red light bends the least and violet light bends most when passed through prism.
10.
Atmospheric refraction is responsible for twinkling of stars, advance sunrise and delayed
sunset.
11.
The blue colour of light, colour of water in deep sea, reddening of the sun at sunrise &
sunset is due to scattering of light.
12.
The scattering of light depends on:(i) Size of the scattering particle
(ii) Wavelength of light
13.
The scattering of blue colour (shorter wavelength) is more then the red colour.
14.
At noon, the sun appears white as only a little of blue and violet colour are scattered.
15.
In the absence of atmosphere, sky appears to be black. (no scattering of light)
QUESTIONS
1 mark questions :1.
Name a light sensitive part of the eye where image of an object is formed.
(444)
X-Science (E.M.)
2.
Name the transparent membrane through which light enters the eye.
3.
What are light sensitive cells?
4.
What type of image of an object is formed on the retina?
5.
What type of signals are generated & sent to the brain by light sensitive cells of retina?
6.
Name the disease in which crystalline lens of human eye becomes opaque.
7.
Define the term power of accommodation in eye.
8.
What is dispersion of light?
9.
What is the value of near point least distance of Distinct vision & the far point of human
eye / range of vision?
10.
Define angle of deviation.
11.
Define angle of Prism.
12.
In visible spectrum, which colour has longest wavelength.
13.
What is Tyndall effect?
14.
Give one main difference between the lens of a human eye and the lens of the camera.
15.
Which phenomenon is responsible for the formation of a rainbow?
16.
Why is a normal eye is not able to see clearly the object placed closer than 25cm?
17.
In which type of eye defect far point of eye gets reduced?
18.
In which type of eye defect near point of eye becomes more then 25cm?
19.
Why does sky appear dark to the astronaut?
20.
Which phenomenon is responsible for increasing the apparent length of the day by four
minutes?
2 mark questions :21.
How does eye control the amount of light entering it?
22.
Why does sky look blue?
23.
Explain the phenomenon which causes twinkling of star.
24.
Why does a ray of white light split up into different colours on passing through a glass
prism?
25.
The sun appears to be red at the time of sunset & sunrise. Give the reason.
26.
A short sighted person cannot see clearly beyond 5cm. Calculate the power of lens
required to correct his vision to normal.
27.
Why do we see stars higher than their actual position?
28.
Why doesn’t planets appear twinkling?
(445)
X-Science (E.M.)
29.
In dispersion of white light through prism, which colour deviates most & which least?
Why do they deviate differently?
30.
On what factors does the colour of the scattered light in Tyndall effect depend?
31.
Why sun appears flattened at sunrise or sunset at noon?
32.
How does the size of particulates in the atmosphere affects scatternig of light?
33.
What is the direction of rainbow formation? What is the position of red colour in a
rainbow?
34.
Why danger signals are red?
35.
Why do you take time to see objects when you enter a dim lighted room from outside
in the sun?
36.
How are two eyes are more helpful for us to see as compared to one?
37.
Which type of lens is present in human eye? If we increase a distance of an object from
the human eye; what will happen to the image distance?
3 marks questions :38.
Near point of a hypermetropic eye is at 1m. Find the focal length, power & nature of lens
used to correct this defect.
39.
The far point of a myopic person is 80cm in front of the eye. What is the nature & power
of lens required to correct the problem?
40.
Draw a labelled diagram of rainbow formation. Also explain the phenomenon of rainbow
formation.
5 marks questions :41.
Draw a labelled diagram of human eye & explain the working of each part of it.
42.
Name three defects of vision with the help of the diagram. Explain the reasons and
corrections of these defects.
(446)
X-Science (E.M.)
Chapter - 12
Electricity
Points to remember:I=
Q
t
1.
Electric current in a conductor is due to flow of electrons.
2.
Conventionally the direction of current is taken opposite to the direction of flow of electrons.
3.
The SI unit of current is ampere. The current is measured by ‘ammeter’ which is always
connected in series to the circuit.
4.
Resistance of a conductor is the obstruction to the passage of current through the
conduction. The SI unit of resistance is ohm. It is resistance which controls the current.
5.
Ohm’s law states that electric current flowing through a metallic wire is directly proportional
to the potential difference V across its ends provided its temperature remains the same.
Vα I
6.
V = IR (Resistance R is constant)
The resistance depends:(i) Directly on length (l)
(ii) inversely on area of cross-section (A)
10 –8Ωm – 10 –6 Ωm
(iii) On the material of wire.
7.
When the resistances are connected in series the resultant resistance Rs = R1+R2+R3 +
- - - - - - and thus greater than any individual resistance.
8.
Electrical potential at any point is the work done in moving unit positive charge from
infinity to that point in an electrical field.
9.
The electrical potential difference between two points in an electric circuit carrying current
is the work done in moving unit positive charge from one point to another.
10.
The SI unit of potential difference is volt. Potential difference is measured by voltmeter
which is always connected in parallel.
11
The SI unit of resistivity is ohm-meter. It is a characteristic property of the material. The
metals and alloys have very low resistivity (
very high resistivity.
) where as insulator have
(1012 Ωm – 1017 Ωm ). Resistivity ( ρ) =
RA
l
12.
The current flowing through each resistor in series arrangement is same.
13.
When the resistors are connected in parallel the resultant resistance R P is given by
1
1
1
1
=
+
+
+- - - - RP
R1 R 2 R 3
(447)
X-Science (E.M.)
Thus resultant resistance in parallel is always less than individual resistance.
14.
SI unit of electric charge is coulomb (c)
1 Coulomb Charge = Charge of 6 x 1018 electrons.
15.
The potential difference across each resistance is same in parallel arrangement.
16.
The amount of heat ‘H’ generated by an electric current ‘I’ flowing through conductor of
resistance ‘R’ for a period ‘t’ sec. is given by a relation.
H = I 2 Rt Joules
H = VIt Joules
H=
V ²t
R
This is also known as Joule’s law of heating.
17.
For an electric bulb metal like tungsten having high melting point ( 33800C ) is used. It is
filled with gases like nitrogen, argon. (Chemically inactive)
18.
The fuse wire has low melting point and is made of an alloy.
19.
V2
The electric power P is given by P = VI = I R =
The SI unit of electric power is watt.
R
20.
The commercial unit of electrical energy is kilowatt hour (kWh)
2
1KWh = 3.6×106 J
21.
Nichrome is an alloy of Nickel, chromium, manganese & iron metals.
22.
A continuous path between the terminals of a source of electricity i.e. cell or battery is
called an electric circuit.
23.
Conductivity is inversely proportional to resistivity.
24.
Resistivity of a material depends on the nature of the material.
QUESTIONS
Very short answer questions carrying 1 mark each:1.
Define electric current & write its S.I. unit.
2.
What is the S.I. unit of charge? Define it.
3.
How many electrons are there in one coulomb of charge?
4.
Define potential difference (P.D.) & write its S.I. unit.
5.
Name the symbols used in electric circuit.
(i)
(ii)
(448)
X-Science (E.M.)
6.
What is resistance? Give its S.I. unit.
7.
What happens to the current in the circuit if its resistance is doubled?
8.
Two wires of same material and same cross – sectional area of length 10cm & 20cm.
Which will have more resistance?
9.
Two wires of same material & cross – sectional area of length 10cm. & 20cm. Which will
have more resistivity?
10.
Name the instrument used for measuring (i) Potential Difference (ii) Current.
11.
Name the instrument used to change the resistance of the circuit.
12.
Name the component used to regulate current without changing the voltage.
13.
How will you connect voltmeter & ammeter in electric circuit?
14.
The area of cross – section of wire P is double that of Q (of same material & length)
Which will have more resistance?
15.
The area of cross - section of wire P is double that of Q (of same material & length)
which will have more resistivity?
16.
Define Ohm’s law.
17.
Give an example of material used for domestic electric wiring.
18.
Define Electric power. Write its S.I. unit.
19.
Define 1 watt.
20.
What is commercial unit of energy?
21.
Name the metals used for making fuse wire.
22.
Define 1 Joule.
23.
What is function of rehostate?
24.
Which metal is used for making the filament of bulb?
25.
Relate kilowatt hour with mega joule.
26.
Identify the insulator among the following :–
Rubber, Graphite, Glass, Water
27.
Consider the unit volt, ohm and ampere. Write the relation between them.
28.
Which will have higher resistivity out of conductor and insulator?
29.
On the basis of resistivity which of the following is a better conductor?
Tungston
5.20 x 10–8ohm meter
Copper
1.62 x 10–8ohm meter
30.
Which metal have higher resistivity?
31.
Name two applianaces where heating is undesirable.
(449)
X-Science (E.M.)
32.
Why we use copper and aluminium wire for transmission of current?
2 mark questions :33.
Why do we use alloy in heating appliances?
34.
Why do we fill gas in a bulb? Give an example.
35.
One wire is cut into three equal parts and then connected in parallel, how will:(i) resistance
(ii) resistivity get affected?
36.
What are the disadvantages of series arrangements for household circuits?
37.
On what factors does the resistance of the material depend?
38.
An electric iron consumes 1KW electric power when operated at 220V, calculate the
value of fuse wire one should use in such case.
39.
Why do we use parallel circuit arrangement for domestic wiring?
40.
8ohm resistance produces 200J heat each sec. Find the potential difference across the
resistor?
41.
A heater draws a current of 15A from the main line for 15 minutes. Calculate the amount
of charge that flows through the filament.
42.$ How many electrons will flow for charge of 5C?
43.$ Calculate the resistance of conductor the current flowing through it is 0.2A. When the
potential difference is 0.8Volt.
44.$ Which lamp has higher resistance 50w lamp or 25w lamp?
45.$ Calculate the area of cross section of a wire a length 4m and resistance 23ohm. The
resistivity of the material of wire is 1.84x10–6ohm meter.
3 marks questions :46.
Discuss briefly three applications of heating effect of current.
47.
State ohm’s law. Draw circuit diagram for its verification.
48.
A heater wire whose power is 4KW is connected to 220 V source calculate:(i) Electric current in the circuit
(ii) Resistance of heater
(iii) Energy consumed in 2 hours.
49.
An electric heater connected to a 220V line has two resistance coil, each of 22 ohms
resistance. They may be used separately, in series or in parallel. What are the currents
in three cases?
(450)
X-Science (E.M.)
50.
In which of the following case energy consumption is more? (i) A 250W T.V. set runs for
one hour. (ii) An electric iron of 1000W is used for 10min.
51.$ A lamp of 100W at 220V & other of 60W at 220V are connected in parallel to electric
mains supply. Calculate the total current drawn from the line?
52.$ A wire of 8 ohm resistance is double on it. Calculate the new resistance of wire.
53.$ A 400W refrigerator operates for 16hrs/day, calculate the cost to operate it for 30 days
at Rs. 3 per KWhr.
54.$ Find the equivalent resistance in combination as shown:-
55.$ Calculate the effective resistance between P and Q.
56.$ How many resistors of 88 ohm are connected
(in parallel) to carry 10A on 220V line?
5 marks questions :57.
(i) State the law which governs the strength of current & potential difference applied
across conductor. Illustrate the law graphically.
$ (ii) Three resistances each of resistance 10 ohms are connected in turn to obtain:(a) Minimum resistance
(b) Maximum resistance.
Calculate the effective resistance in each case & their ratio.
58.$ Calculate:(i) Resultant resistance
(ii) Total current
(iii) Voltage across 7 ohms resistor.
(451)
X-Science (E.M.)
Chapter - 13
Magnetic Effects of Electrical Current
Points to remember:1.
A magnetic field is a vector quantity, the direction of magnetic field is the direction in
which north pole of a compass needle moves inside it.
2.
The crowding of the magnetic field lines indicates the strong magnetic field.
3.
The magnetic field lines never cross each other as there can’t be two directions of
Magnetic field at a given point.
4.
Every current carrying conductor whether straight or circular has a magnetic field around
it.
5.
The direction of the magnetic field associated with a current carrying straight conductor
is given by right – hand Thumb rule.
6.
A solenoid carrying electric current behaves like a bar – magnet.
7.
A device consisting of solenoid with an iron core (to increase the strength of magnetic
field) is known as electro magnet.
8.
A mechanical force acts on a current carrying conductor when it is placed in a magnetic
field. The direction of the force depends upon.
(i) Direction of the current
(ii) Direction of magnetic field.
To find direction of force Fleming’s left hand rule is used.
9.
An electric motor is based on the principle that when current carrying conductor is
placed in a magnetic field it experiences a force.
10.
The phenomenon of electromagnetic induction is production of induced current in a coil,
when the coil is moved perpendicular to the lines of magnetic field.
11.
The direction of induced current is given by Fleming’s right hand rule.
12.
A generator converts mechanical energy into Electrical energy. This works on the principle
of electromagnetic induction.
13.
In India A.C. voltage is supplied to domestic use at 220V, having frequency of 50Hz.
14.
Domestic electric circuit has three wires; live (red), neutral (black), earth (green).
15.
Fuse – wire is always connected to live – wire.
16.
Earthing is done to save ourselves from electric shock.
17.
Magnetism has got important uses in medicine.
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X-Science (E.M.)
QUESTIONS
1 mark questions :1.
Why does a compass needle get deflected when brought near a metallic wire carrying
current? Who invented the effect?
2.
A straight metallic wire carrying current is bent in the form of a circle; how does the
magnetic field get affected at a particular point?
3.
What is the direction of magnetic field lines outside a bar magnet?
4.
Classifiy the following quantities into scalar and vector quantities.
(a) Electric currect
(b) Magnetic Field
(c) Resistance
(d) Electric power
5.
How will the magnetic field change when the distance from the current carrying conductor
is increased?
6.
State right hand thumb rule.
7.
What is the S.I. unit of magnetic field?
8.
What does crowding of magnetic field lines indicate?
9.
What is a solenoid?
10.
What is the use of inserting a soft iron core inside a current carrying solenoid?
11.
Name the path along which hypothetical free north pole would tend to move when
placed in a magnetic field?
12.
What is the value of magnetic field inside a long straight solenoid carrying current?
13.
Name the magnet produced on inserting a soft iron core inside a current carrying solenoid?
14.
How does magnetic field change inside a long straight solenoid carrying current?
15.
Name a device based on principle of electromagnetic induction.
16.
Name two sources of direct current (D.C.)?
17.
Write difference between Direct Current (D.C.) and Alternating Current (A.C.)
18.
Name two devices into which electric motors are used.
19.
What is the frequency of domestic A.C. supply in India?
20.
What type of current is used in household supply?
21.
What type of current is given by a cell?
22.
What is Fleming’s right hand rule?
23.
Indicate the colours of neutral & live wire.
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X-Science (E.M.)
24.
What do you mean by short circuiting of the circuit?
25.
What does arrow of magnetic field line indicate?
26.
To which wire do you connect fuse wire in house–hold electricity?
27.
Give the sequence of transformation of energy in the functioning of electric motor.
28.
What happens when we connect too many appliances to a single socket?
29.
Name two devices using permanent magnets.
30.
Which of the two requires a thin fuse wire; to draw 5A or 15A of current?
31.
Name two organs in the human body where magnetic field is quite significant.
32.
Write one important technique based upon magnetism for medical diagonosis.
33.★ Mention one cause for overloading other then accidental hike in the voltage supply.
34.★ What will be frequency of an alternating current if its direction changes after every 0.01
second?
2 marks questions :35.
A current in horizontal power line is from east to west. What is the direction of magnetic
field? at a point directly
(i) Below it
(ii) Above it.
36.
What is the pattern of the magnetic field at the centre (ii) near portion of circular coil?
37.
What will be the direction of force acting on the electron
when it enters a magnetic – field at right angle to it as
shown.
38.
How do we connect earth wire in a house?
39.
Give one example each of the use of (i) Permanent magnet (ii) Electromagnet.
40.
State the principle of Dynamo.
41.
State the principle of electric motor.
42.
Name the device used in head lights of scooter, on what principle does it work?
43.
Why do we prefer A.C. for transmission to long distances while most the applications are
based on D.C.?
44.
Mention two serious hazards of electricity.
Magnetic
Field
Electron
3 mark questions :45.
How will the magnetic field produced in a current carrying a circular coil change if we:(454)
X-Science (E.M.)
(i) increase the value of current
(ii) Increase the distance from the coil
(iii) Increase the no. of turns of coil.
46.
What are the various methods to induce Electric current in the coil?
47.
Draw labelled diagram of electric motor.
48.
Draw labelled diagram of Dynamo.
49.
What is an armature? What is the use of split rings?
50.
What is the colour used in insulation of earth wire? What is the use of earth wire?
5 mark questions :51.
Draw the magnetic field due to current in a circular coil and a solenoid.
52.
Mention important characteristics of the magnetic field produced by each.
53.
Draw a schematic diagram of domestic wiring system and write its main features.
(455)
X-Science (E.M.)
Chapter - 14
Sources of Energy
Points to remember:1.
Conservation of energy : Energy can neither be created nor be destroyed.
2.
Slurry left behind after use of Biogas contains manure (rich in Nitrogen & Phosphorus).
3.
In thermal power plant, steam runs the turbine (mechanical energy) to generate electricity.
4.
Biogas : Decomposition of vegetables wastes, plants, crops, cowdung in the absence of
oxygen. (Gobar gas by anaerobic micro organism)
5.
There are limitations of using wind energy, sea energy, solar energy.
6.
In India, fossil fuel is main source of energy. (in danger of getting exhausted)
7.
Many of sources ultimately derive their energy from the sun.
8.
A slurry of cow – dung & water is made to decompose by anaerobic micro – organism
slurry generate Bio-gas.
QUESTIONS
1 mark questions :1.
What is the law of conservation of energy?
2.
What is the major fuel used to generate electricity?
3.
What is the principle of turbine?
4.
What is the principle of dynamo?
5.
What is green house effect?
6.
What is acid rain?
7.
Thermal power plants are set up near coal or oil fields, why?
8.
What is the principle of hydrogen thermal power plant?
9.
What is Bio – Mass?
10.
Which is the main gas present in Bio – gas?
11.
What is the slurry?
12.
What is the use of slurry left behind in Bio – gas?
(456)
X-Science (E.M.)
13.
Why do we blacken the outer surface of solar – cooker?
14.
Name the device which convers sunlight into electricity.
15.
What are various limitations of solar cell?
16.
What is wave energy?
17.
What is Geothermal energy?
18.
What is Solar Panel?
19.
Name a material used for interconnecting solar cells for making solar – panel.
20.
What is main source of energy in artificial satellite & space probes?
21.
Name two types of energy which do not relate to the sun.
22.
Name the part of the box type solar cooker which allows the sun rays to enter the box
but prevent them from escaping.
23.
Name two appliances that use solar energy directly.
24.
Name the non renewable source of energy other then fossil fuel.
25.
Name the semi conductor material which is used for making solar cell?
26.
Out of C.N.G and hydrogen, which gas is cleaner?
2 marks questions :27.
What is the good source of energy?
28.
What are renewable sources of energy? Give two examples.
29.
What are nonrenewable sources of energy. Give two examples?
30.
Classify the following into renewable and non-renewable sources of energy :–
coal, wind, tides, petroleum, wood, natural gas
31.
What are disadvantages of burning fossil fuel?
32.
Name two dams having strong opposition for their construction.
33.
What are the main gases present in Bio – gas?
34.
What are advantages of Bio – gas?
35.
What are limitations of wind energy?
36.
What are advantages of using wind energy?
37.
What are advantages of solar cell?
38.
What is tidal energy?
(457)
X-Science (E.M.)
39.
What are various energy potential from the sea?
40.
What kind of mirror one should use in solar cooker & why?
41.
How can we overcome energy crisis?
42.
Compare the limitations of energy in wind and sunrays.
3 marks questions :43.
With the help of diagram, explain the working of hydro power plant.
44.
What are various problems in constructing dams to generate electricity?
45.
What is Bio – gas? Explain working of bio gas plant with the help of diagram.
46.
List four forms of energy that you use very commonly every day. From where do we
derive these forms of energy?
(458)
X-Science (E.M.)
Chapter - 15
Our Environment
Points to remember:1.
All organisms like plants, animals, microbes, human beings, interact with physical factors
and maintain a balance with nature.
2.
Green plants (producers) fix solar energy and makes it available to other organisms.
3.
Consumers have been divided into herbivores, carnivores, omnivores and parasites.
4.
Along with directional flow of material occurs energy – flow in food chain and food web.
5.
Only 10% of energy is transferred from one to another trophic level, and rest of the
energy is lost to the environment thus limiting the number of trophic levels in food chain.
6.
Chloro flouro carbons deplete ozone layer which shields us from harmful ultraviolet
radiations.
7.
Generated waste can be either biodegradable or non – biodegradable.
8.
Waste generated by us and its disposal has become a serious environmental concern.
9.
Recently the court of justice banned the use of polybags, but the issue has raised
secondary environmental concern (like deforestation by using paper bag etc.)
QUESTIONS
1 mark questions :1.
Write any one significance of biochemical cycles?
2.
Define environment.
3.
According to the sustenance from environment, organisms can be grouped into which
three categories?
4.
Name any two groups of producers.
5.
Define consumers.
6.
Write the two raw materials for making food, used by living organisms of first trophic
level.
7.
Explicate the principle of food web.
8.
Which of the following are more numerous in a food chain :–
(i) Secondary consumer
(ii) Tertiary consumer
(459)
X-Science (E.M.)
9.
Define biological magnification.
10.
Write the names of two decomposers.
11.
Define global warming.
12.
Write one ill effect of exposure to ultraviolet rays.
13.
Which component of sunlight is vital for formation of ozone?
14.
As a step to control pollution ‘Kulhads’ were used on a large scale. What was the ill
effect of this practice?
15.
A food chain consists of grass, lion and rabbit. In this food chain, which organism will
transfer maximum energy?
16.
Which of the following are Biodegradable; plastic toys, cow dung, aluminium foil and
cotton?
17.
Name the programme that froze CFC production in 1986.
18.
Expand UNEP.
19.
Which is greater – energy lost to the environment or energy transferred to next trophic
level?
20.
Write a common feature between a food chain and energy flow in nature.
21.
How is packaging related to increase in non biodegradable waste?
22.
Burning the coal yields energy, but if try to eat coal we will not get any energy. Why?
2 marks questions :23.
Distinguish between biodegradable and non biodegradable wastes. Cite examples.
24.
Why is a plastic bag is called non-biodegradable while a paper is not?
25.
Choose a biotic components comprising physical factors from the following : Rose, Soil,
Leaf, Potato, Mountain, and Atmospheric pressure.
26.
Name any four ecosystem.
27.
Differentiate between natural and artificial ecosystem.
28.
Why decomposers are necessary in environment?
29.
Distinguish between food chain and food web.
30.
Draw a pyramid showing four trophic levels.
31.
Consider a food chain:Grass → Insect → Frog → Snake → Hawk
900KJ
(460)
X-Science (E.M.)
How much energy is available at the first trophic level and fifth trophic level respectively.
32.
Enlist two uses of CFCS. Write their harmful effect.
33.
What will happen if all the snakes are eliminated from the following
Grass
Insect ¾ ¾
® Frog ¾ ¾
® Snake ¾ ¾
® Hawk
34.$ Is the road near your school a part of ecosystem? Explain
35.$ A neem tree is a producer but not the bread mould found on bread we eat. Give reasons.
36.$ Describe the process of decomposition.
37.$ Pesticides are useful to farmers, yet considered
as pollutants. Give reason.
38.$ Energy stored in the body of lion is the energy
coming from sun. Justify.
39.$ In the diagram given here, which organism will
get maximum energy apart from green plants?
¾¾
®
40.$ Observe and study the following diagram
carefully. Enlist the organism having same
attributes as the peacock.
3 marks questions :41.
Enlist various categories of consumers giving
examples of each.
42.
Describe the 10% law of flow of energy using
example. What percentage of solar energy
is captured by plants in terrestrial ecosystem
that falls on their leaves?
43.
Write two informations obtained from the
energy flow diagram.
44.★ A farmer cultivates wheat crop in his agricultural
field. Explain the interlinks of Biotic and
abiotic factors in this case.
(461)
X-Science (E.M.)
45.★ Explain how the pesticide used in the field reaches inside the body of a tertiary consumer?
46.
Recently the honourable court of justice banned the use of polythene bags. Do you
support the step. Explicate with reasons.
47.
Correlate the natural replinishment of soil and decomposers.
5 marks questions :48.
Make two food chains and a food web from the following set of living organisms : Grass,
Lion, Vulture, Deer, Insect, Snake. Identify the tertiary consumer in both of the food
chains.
49.★ Identify a deadly poisonous gas ‘X’ found at higher level of atmosphere which shields
the surface of earth from harmful radiations from the sun. Write its chemical formula and
equation of its formation. Why is damage to the ‘X’ layer a cause of concern? What steps
are beings taken to limit this damage?
50.★ You are involved in a discussion on Interrelationship between environment and life
styles.” with Nagendra and Paramjit. Nagendra is a village farmer and Paramjit is a
owner of a popular showroom. Give the details of issue discussed. Describe the ill
effects of such lifestyles on the environment.
(462)
X-Science (E.M.)
Chapter - 16
Management of Natural Resources
Points to remember:1.
Air, water, soil, forest, wild life, coal and petroleum are considered to be natural resources.
2.
Management of resources is necessary for sustainable development.
3.
3 ’R’ – Reduce, Reuse, Recycle.
4.
Spreading awareness about problems arises due to non judicious harnessing of natural
resources is essential.
5.
Forests are hot spots of biodiversity.
6.
Chipko movement and many other such movements are very important to save our
forests and wild resources.
7.
Management of forest resources has to take into account the interest of various
stakeholders.
8.
For conservation of water resources, constructions of large dams are alternative besides
local water harvesting methods eg. : Khadins; tanks; nadis etc.
9.
The harnessing of water resources by building dams has social, economic and
environmental problems.
10.
Fossils fuels coal and petroleum will be exhausted soon due to limited deposits.
11.
Combustion of coal and petroleum produces poisonous gases like CO2, NO2, SO2
and CO. Which pollutes the environment and are responsible for acid rain.
12.
Need to use these resources judiciously.
QUESTIONS
1 mark questions :1.
What is a natural resource? Give two examples.
2.
Define sustainable development.
3.
What does the three R’s stand for to save the environment?
4.
What do you mean by water – shed management?
5.
Name the award recently instituted by govt. of India in the memory of Amrita Devi
Bishnoi.
6.
Name the bacteria whose presence in the water indicates its contamination with disease
causing microbes.
(463)
X-Science (E.M.)
7.
Define Bio – Diversity.
8.
Why fossil fuels should be used judiciously?
9.
Which canal has brought greenary to the areas of Rajasthan?
10.
State the advantage of constructing a dam across a river?
11.
Name the place where “Chipko Andolan” organised.
12.
Name the main constituents of coal and petroleum.
13.
Name the gas responsible for global warming.
14.
Who was the leader of Chipko Andolan?
15.$ Write the main aim of conservation of different life forms.
16.$ We should try to preserve the biodiversity we have inherited. Why?
2 marks questions :17.
How mining causes pollution?
18.
Which is better : recycle or reuse? Give reasons.
19.
Write the aims and two advantages of water shed management.
20.
Name the main stakeholders in the management of forest resources.
21.
Name the major industries based on forest products.
22.
Why is it necessary to conserve forest and wildlife?
23.
State two disadvantages of constructing a dam.
24.
A tribe is living near the forest. Name two things which they will commonly use from
forest.
25.
The forest department is managing the forests in India. How does this management
affect the people living in and around forest?
26.
How human activities cause damage to forests?
27.
Give an example of people’s participation in the management of forests.
28.
Write two advantages of classifying sources as renewable and non renewable.
29.$ Name the products of combustion of coal and petroleum. How do they effect our
environment?
3 marks questions :30.
What is water harvesting? Name any two indegenous methods for water harvesting.
31.
Explain 3 R’s with one example of each.
32.
Write main uses of fossil fuels.
(464)
X-Science (E.M.)
33.
Mention three ways to reduce the consumption of coal and petroleum.
34.
“Save the Narmada movement” activists are protesting to certain problems. What are
those problems?
35.
What are the advantages of water stored in ground?
Long answer questions carrying 5 marks each:36.
(i) Write the pollutants emmited by the combustion of coal and petroleum.
(ii) Give ways in which you can contribute towards environment – friendliness.
37.
What is the rain water harvesting? How can it be done at local level? What are its
benefits besides ground water recharging?
38.
(1) List any four measures of conserving forest and water.
(2) What are the ill effects of deforestation on environment?
(465)
X-Science (E.M.)
ANSWERS
Chapter - 1 Chemical Reactions and Equations
1.
It changes into white powder.
2.
breathing of substances
3.
Endothermic
4.
Combination
6.
Water decomposes into hydrogen and oxygen.
8.
Gold (Au)
10.
Endothermic
11.
Displacement reaction
12.
Antioxidants
16.
g = gaseous, l = liquid, aq = aqueous and s = solid, states.
17.
Cu < Fe < Zn
18.
example –
19.
Brown fumes, Nitrogen dioxide
21.
Air tight containers; Refrigeration
24.
To avoid oxidation
29.
(i) BaCl2 + K 2 SO4 → BaSO4 + 2 KCl
CaO + H 2O → Ca(OH ) 2 + Heat (change in temp.)
(ii) NaCl + AgNO3 → NaNO3 + AgCl
(iii) Ca(OH ) 2 + CO2 → CaCO3 + H 2O
30.
(i) ZnO = reduced, C = oxidised, C = reducing agent, ZnO = oxidising agent
(ii) CuO = reduced, Hydrogen = oxidised, H2 = reducing agent, CuO = oxidising agent
(iii) MnO2 = reduced, HCl = oxidised, MnO2 = oxidising agent, HCl = reducing agent.
Chapter - 2 Acids, Bases and Salts
1.
Litmus, Turmeric
2.
Methyl orange, Phenolphthalein
3.
Pink
4.
Olfactory
5.
Vanilla, Onion or clove
6.
Hydrogen
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X-Science (E.M.)
8.
Hydrochloric acid
9.
Antacids
10.
Methanoic acid
11.
Hydrogen
12.
Less then 5.6
14.
It leaves an acid inside
15.
Bases soluble in water
16.
Heat generated cause the mixture to splash out and cause burns
17.
Give H+ ions only in presence of water.
19.
Decreases
22.
Calcium sulphate hemihydrate
23.
Becomes colourless
24.
Decreases below 6
25.
CaSO4 ,½ H 2O
27.
Calcium oxychloride
29.
A<B<C
31.
Chlor alkali
34.
(i) 1.2
37.
It is neutral and does not generate H + ions.
38.
Pink → colourless
40.
5 molecule
45.
Sodium hydrogen carbonate, CO2
46.
Baking powder
50.
Acetic, oxalic and tartaric acid
(ii) 2.2
(iii) 7.4
(iv) 10
Chapter - 3 Metals and Non metals
1.
Malleability is a property of metals through which they can be drawn into their sheets.
2.
Gold is the most malleable metal
3.
Ductility is a property of metals through which they can be drawn into thin wires.
4.
Potassium and sodium
5.
PVC is shock proof
6.
The metals that produce sound or striking a hand surface
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X-Science (E.M.)
7.
Mercury and Bromine
8.
Lustorous = Iodine and non lustorous = Sodium
9.
Metals form basic oxides while non metals form acidic oxides.
10.
Diamond
11.
Silver and Gold
12.
Because of their high reactivity to oxygen leading to fire.
13.
Most reactive = Ca ; least reactive = Hg
14.
Mg and Mn
15.
Dazzling white flame
16.
Ionic bond
17.
By Electrolytic reduction
18.
Carbon
19.
Minerals from which metal can be profitably extracted are called ORES.
The impurities like soil, sand etc present in ores are called GANGUE
20.
Aluminum
21.
Impure metal = Anode
22.
Acidified copper sulphate solution
23.
An alloy of murcury with other metal and non metal
24.
Settled insoluble impurities at the bottom of anode.
25.
Because HNO3 is a strong oxidising agent.
26.
Due to formation of hydrogen gas which stick to metal surface.
27.
Roasting :– Heating strongly in the presence of excess of air.
28.
Green coloured compound Copper carbonate, Metal = copper
29.
Due to strong force of attraction between +ve and –ve ions.
30.
ions forms only in solutions
31.
Formula A2B
32.
Reactivity series is a list of metals arranged in order of their decreasing activity.
pure metal = Cathode
Au < Cu < Fe < Zn < Al < Ca
33.
Because it shows basic as well as acidic properties e.g. Al2O3
34.
Solder, constituents - lead and tin
35.
i, sodium chloride – Na + Cl → [ Na ] [Cl ]
36.
Painting and Galvanising
37.
Gallium & Cesium due to low melting points.
+
–
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X-Science (E.M.)
38.
Because it displaces metals of law reactivity from their compounds.
39.
A process of coating thick layer of Al2O3 on aluminium.
40.
Electrolytic refining
41.
Heat
(i) ZnCO3 ( Solid ) 
→ ZnO ( Solid ) + CO2 ↑
Heat
(ii) 2 HgS ( Solid ) + 3O2 ( g ) 
→ 2 HgO( Solid ) + 2 SO2 ↑
(iii) 3MnO2 ( Solid ) + 4 Al ( Solid ) → 3Mn + 2 Al2O3 ( Solid ) + Heat
42.
Homogenous mixture of a metal with another metal or non metal.
Stainless steel - Fe, Ni, Cr
Bronze - Cu, Sn
43.
Thermite reaction Fe2O3 + 2 Al → 2 Fe + Al2O3 + Heat
Used to join railway tracks
44.
(i) 3Fe + 4 H 2O → Fe3O4 + 4 H 2 ↑
(ii) Ca + 2 H 2O → Ca (OH )2 + H 2 ↑
(iii) Cu + O2 → 2CuO
45.
(i) Because metals lose electrons to complete its octat.
(ii) Copper is less reactive than Zinc.
46.
47.
O2
Concentration of ore → Roasting 
→ Oxide of metal → Reduction to metal →
Purification of metal.
Cinnabar ( HgS ) , By heating
Heat
2 HgS + 3O2
2HgO
Heat
3HgO + 2SO2 ↑
2Hg + O2 ↑
48.
Metals which easily lose electrons are more reactive.
49.
(i) Beacuse Zinc is most reactive metal among these.
50.
Gold never corrode where as iron always corrode.
51.
(i) Sodium
(ii) 4 Na + O2 → 2 Na2O
Na2O + H 2O → 2 NaOH
(iii) Electrolytic Reduction
52.
(i) Copper
(ii) By Roasting
(iii)
Heat
2Cu2 S + 3O2 
→ 2Cu2O + 2 SO2 ↑
Heat
2Cu2O + Cu2 S 
→ 6Cu + SO2 ↑
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X-Science (E.M.)
Chapter - 4 Carbon and its Compound
1.
Co-Valent Bond
2.
Four
3.
Unique ability to form bonds with other atoms of carbon giving rise to large molecule is
called catenation.
4.
The compounds in which carbon has double or tripple bonding.
5.
Because of double or tripple bonding
6.
–CH2
7.
14u
8.
(i) Alcoholic
(ii) Ketonic
9.
(i) Chloroethane
(ii) Methanal
10.
Saturated Hydrocarbon
11.
Un-saturated Hydrocarbon
12.
CO2 and H 2O
13.
It freezes in winter/ cold climate
14.
CO2
15.
Ni
16.
Yellow flame
17.
H 2 SO4
18.
In hydrocarbon compounds, the elemants replacing hydrogen is referred as heteroatom
eg. helogens.
19.
20.
Hydrocarbons having similar structures and similar properties. Features no. of atoms
difference in two successive ___ us CH 2 and difference of molecular mass is 14 U.
21.
Leads to deposition of carbon black.
22.
Saturated - single bonding
23.
C3 H 6 and C2 H 2 because of unsaturated hydrocarbons.
24.
(i) C6 H 6
25.
(i) Propanoic acid (ii) Butyne
26.
Compounds with identical molecular formula but different structures.
27.
Compounds of carbon and Hydrogen
(i) CnH 2 n + 2
Unsaturated - double & tripple bonding
(ii) C2 H 5COOH
(ii) C2 H 2n
(470)
X-Science (E.M.)
28.
H 2 gas is evolved.
→ 2CH 3CH 2O – Na + + H 2 ↑
2 Na + 2CH 3CH 2OH 
29.
A - Ethanol B - Athanoic Acid
Acidic K 2Cr2O7 + Heat
CH 3CH 2OH
CH 3COOH
30.
Addition of hydrogen to vegetable oils in the presence of catalysts. To convert vegetable
oils into fats.
31.
Substitution reaction. CH 4 + Cl2
32.
White precipitae of Ca + + and Mg +2 ions, in hard water with soap.
33.
(i) A
34.
Sweet smelling compounds, formed by the action of ethanoic acid and ethanol in the
sun light
CH 3Cl + HCl
(ii) B
presence of conc. H 2 SO4
35.
(i) C6 H12
(ii) CH 3CH 2CHO
37.
(i) CH 3CH 2OH
R
(ii) R
Conc. H 2 SO4
CH 2 = CH 2 + H 2O
Heat
H H
R
Ni
R
H2
C=C
(iii) C4 H 9Cl
R–C –C – R
R
R
(iii) CH 3COOH + NaOH 
→ CH 3COONa + H 2
40.
em H 2 SO4 + Heat
(i) Removal of molecular of water, CH 3CH 2OH
CH 2 = CH 2 + H 2O
(ii) Formation of ester,
CH 3CH 2OH + CH 3COOH
em H 2 SO4 + Heat
CH 3CH 2COOCH 3 + H 2O
(iii) Alkaline hydrolysis of ester,
O
O
CH 3 – C – OCH 2CH 2 + NaOH 
→ CH 3 – C + ONa + CH 3CH 2OH
41.
Due to formation of scum.
42.
(i) CH 3CH 2OH
conc. H 2 SO4
CH 2 = CH 2 + H 2O
(471)
X-Science (E.M.)
(ii) CH 3CH 2OH
Acidic K 2Cr2O7 + Heat
(iii) CH 3CH 2OH + CH 3COOH
R
43.
Example of Addition -
conc. H 2 SO4 + Heat
C=C
R Ni + H
2
CH 3CH 2COOCH 3 + H 2O
H H
R –C –C – R
R
R
R R
Sun light
Example of Subtraction - CH 4 + Cl
44.
CH 3COOH
CH 3Cl + HCl
(i) ethanoic acid turn into red
(ii) ethanoic acid evolves CO2 ↑
(iii) Both evolve H 2 ↑
45.
(i) Maximum tendency of carbon for catenation is responsible for this.
(ii) For proper supply of oxygen for complete combustion of fuel.
(iii) As detergents are nonbiodegradable.
46.
Complete oxidation is called combustion and end product of combustion are CO2
& H 2O .
47.
A - CH 3COOH
B - CH 3CH 2COOCH 3
C - CH 3COOH
D - CO2
H –N–H
49.
(a) Carbon dioxide - O = C = O (b) Ammonia
[ ]
H
(c) Ammonia Chloride
H
+
H – N – H Cl –
H
(d) CH 3CH 2OH
(e) Unsaturated hydrocarbon
(472)
X-Science (E.M.)
Chapter - 5 Periodic Classification of Elements
1.
Triad
3.
Atomic mass
4.
18 groups, 7 periods
5.
Existence of some elements that had not been discovered
6.
Atomic number
7.
Two
8.
Remain same
10.
Zero
11.
Increases from left to right
12.
Atomic number
13.
Lithium, Beryllium
18.
Groups
19.
Periods
22.
Henry Moseley, Atomic number
25.
Z<Y<X
26.
Same position would be assigned as atomic number is same.
27.
Nitrogen (7) → 2, 5
Phosphorus (15) → 2, 8, 5
Non Metallic
28.
Atomic size will increase due to addition of cell.
29.
Only three triads could be identified
30.
ZnO, Al2O3
33
(a) 17
(b) NaX
(c) Halogen
Chapter - 6 Life Processes
1.
Carbon
2.
When organism use simple substances like CO2 and water to prepare food inside the
body.
3.
Hetrotropic nutrition
4.
Biological catalysts, Amylsae
5.
Peristaltic movements
(473)
X-Science (E.M.)
6.
Chloroplast, chlorophyll
7.
chlorophyll
→ C6 H 12 O6 + 6O2
6CO2 + 6 H 2O 
Sunlight
8.
Salivary Amylase
9.
Small Intestine
10.
Sphincter Muscle
11.
Respiration
12.
Guard cells
13.
Anaerobic respiration, some becteria
14.
Pyruvate
15.
Cytoplasm
16.
Mitochondria
17.
Air, Water
18.
For filtration
19.
Extra cellular fluid used in transportation
.
So that air passage does not collapse
20.
Alveoli
21.
Haemoglobin
22.
Lactic acid
23.
Platelets, blood clotting
24.
Blood pressure decreases
25.
Phloem
26.
Supply of water and minerals prohibited
27.
So that air passage doesn’t collapse
28.
Plants growth, Some animals breathe without showing any external movement
30.
pH in small intestine > 7 and in stomach < 7
31.
Liver (bile juice) and pancreas (pancreatic juice)
32.
Temperature regulation, absorption and upward movement of H2O and minerals
33.
Bile break down large globules of fats into smaller globules of fat so that increasing the
efficiency of enzyme.
37.
lactic acid produced due to Insufficient supply of oxygen.
38.
Immobility and excess of dead tissue.
39.
Acidic medium for pepsin; its presence in stomach signals hunger.
41.
because ventricles have to pump blood into various groups.
( Glu cos e )
(474)
X-Science (E.M.)
42.
(i) both are carbohyderate
(ii) pigments
(iii) respiratory organs
(iv) both are vessals that transport blood
43.
Rat dog whale
–
Not mix
lizard, snake, Pigeon
–
Mix
44.
the alveoli provide surface where the exchange of gases takes place. The walls of
alveoli contain extensive network of blood vessels. Same in nephrons has cluster of very
thin walled capillaries. In the nephrons nitrogenous wastes are removed from blood.
45.
1. Absorbtion of light energy by chlorophyll
2. Conversion of light energy to chemical energy and water molecule
3. Reduction of CO2 to carbohyderates
46.
49.
HCl
–
Acidic Medium
Mucous
–
lubricating wall
Pepsin
–
protein → peptone
Incomplete digestion
Absorption
Circulation
51.
56.
Excess water
–
transpiration
Oxygen, waste
–
Surface of leaves or fall off of leaf
Resin and gum
–
Bark stem, branches and soil
Refer fig. 6.6, pg. 99 (N.C.E.R.T)
(a) Liver – emulsification of fat, alkaline medium, storage of glycogen
(b) Pancreas - pancreatic juice
(c) (i) small intestine
58.
(ii) large intestine
Root pressure, water column, transpiration pull.
Chapter - 7 Control and Coordinations
1.
Brain
2.
Pons, medulla, spinal cord.
3.
Cerebellum
4.
Medulla of hind brain and mind brain
5.
Change in shape and arrangement of proteins in muscle cells.
(475)
X-Science (E.M.)
7.
Fore brain
8.
Can't control salivation easily by thinking about it even if we want to.
9.
Bony skull, shock absorbing fluid.
10.
Removing hand immediately on touching a hot metal.
11.
Mid Brain
12.
Taste and smell
14.
Relay neuron
15.
Peripheral nervous system
16.
Spinal and cranial nerves.
17.
Spinal chord
18.
Forebrain
19.
Brain and spinal cord
20.
Auxin and gibberellins
21.
Skin and digestive system.
22.
Heart beats faster
23.
Deficiency causes dwarfism
24.
Boys - testosterone, girls – estrogen
25.
Above the kidneys
26.
Proteins
27.
Growth dependent movements
28.
Water
29.
Shoot tips
30.
Immediate reaction can’t be done
31.
Forebrain
32.
Pancreas
Amylase / trypsin / lipase
33.
(i) Auxin
(ii) Cytokinis
34.
(i) Growth Hormone(ii) Pituitary gland
35.
Adrenaline hormone
36.
Control the blood pressure, vomitting
37.
Consist of dense networks of. intricatly arranged neuron Located at the forward end of
the brain.
38.
Spinal cord control the reaction (immediate) to action (the stimuli)
39.
If plant part movement is due to chemicals. Movement of pollen tubes towards ovulus
(476)
X-Science (E.M.)
40.
Diabeties, Pancreas, blood
41.
Hormones need to be secreted in precise quantities. The timing and amount of hormone
released and regulated by this mechanism.
42.
Limitation - Impulse reaches only those cells having nerve connections and cannot
continually create the transmit electrical impulse.
43.
Advantage - reaches each and every cell regardless of nerve link, demerit - slower.
46.
Hormones are secreted by endocrine glands whereas enzymes are secreted by exocrine
gland.
Chemically some hormones are protiens whereas all enzymes are proteins.
47.
Nastic movements, Not directional - ex. opening of flowers, twirling of tendrills
Curvature movements - Directional
49.
the information is required at the tip of dendrites of nerve cell sets of a chemical reaction
that creates an electric impulse. This impulse travels from dendrite to cell body and to
axon. At the end of axon electrical impulse sets off and release some chemicals. These
chemicals travels through gap and produce electric impulse in dendrites of another
nerve cell.
52.
Endocrine glands are ductless glands
Exocrine glands have ducts
Endocrine glands pour secretions directly in blood.
54.
Iodine, Goitre, swelling in the neck region
Chapter - 8 How to Organisms Reproduce
1.
Copy of DNA + cellular apparatus
2.
Simultaneously divides into many cells
3.
Breaks into pieces, each fragment matures
4.
Regenerative cells
5.
Bryophyllum
6.
Rhizopus
8.
Outside abdominal cavity in scrotum.
9.
low temperature required
11.
uterine wall
12.
Glucose, oxygen
14.
Prevent the release of eggs.
16.
Vas deferens in male, fallopian tube in female
(477)
X-Science (E.M.)
18.
sex selective abortions
23.
asexual reproduction
28.
some bacteria and protozoa
32.
Survival possible without it
38.
thick wall
41.
prevent sperms entry
43.
maintain the number of chromosomes in the progeny.
46.
Better fruits, genetically similar seeds.
49.
drastic variation cause incompatibility of DNA with cellular apparatus, leads to death.
52.
fluid medium, easier morion, nutrition.
55.
Bacterial
–
syphilis, gonorrhea
Viral
–
Warts, AIDS
61.
Papaya, watermelon, hibiscus, mustard
66.
male urethra - both gamatic and urine
female - urine
67.
mango – both sexual mode and vegetative propogation
banana – only vegetative propogation
Chapter - 9 Heredity and Evolution
1.
Sexual reproduction
2.
Survival varies according to the advantage or disadvantage endowed with.
4.
Africa
7.
Proteins
9.
Y
10.
Female
11.
Narmada valley
12.
Ammonite, trilobite
13.
C and D
15.
Complete decomposation of A’s remains
16.
< 7.
17.
F2
19.
Bacteria
20.
Knightia
(478)
X-Science (E.M.)
21.
On chromosomes
24.
natural selection and genetic drift
27.
having nucleus
28.
Dinosaur, Dromaesaur
29.
Compare DNA of different species
30.
DNA sequencing, fossil study, excavating and time dating
34.
Digging, time dating
35.
XX – one X from both
XY – X from mother and Y from father.
39.
(i) Survive in extreme habitats
(ii) fishes have specific habitat
40.
XX – all gametes with X – chromosomes
XY – two gametes with X and two with Y chromosome.
Ratio : 3 : 1
53.
one buried under the hot mud, reason
Chapter - 10 Light - Reflection & Refraction
1.
Convex mirror
2.
Concave
3.
22.5cm
4.
same path
5.
concave
6.
convex
7.
20cm [centre of curvature]
8.
concave
9.
convex
11.
become less
12
M1
13.
away from normal
16.
concave lens
17.
concave mirror
18.
Refraction
19.
zero
20.
it travels in straight path
(479)
X-Science (E.M.)
21.
change in the speed of light
22.
between principal focus and optical centre
24.
(i) 1.50, (ii) 1.31
26.
ray of light from coin (water) bends away from normal
27.
f = 15.3cm, R = 30.6cm
28.
f = 40cm, convex lens
29.
point size image of sun at f; so heat generated due to conc. of sun-rays.
31.
errect and diminished; image moves closer to focus becomes smaller
35.
38.
virtual and erect image in all but-in plane mirror-same size
in concave mirror - magnified
in convex mirror - diminished
39.
v = +30cm, m = –8cm
40.
(i) beyond C, enlarged
(ii) enlarged, behind screen
(iii) small, between f & C, smaller in size
n=
c
= 1.33
u
Chapter - 11 The Human Eye & Colourful World
3.
Present in retina they generate electric signals.
6.
Cataract
9.
25cm to infinity
14.
lens of human eye has flexible aperture
15.
dispersion of light
16.
least distance of distinct vision for normal eye is 25cm and ‘f’ of eye cannot be decreased
below this.
17.
myopia
18.
hypermetropia
19.
no atmosphere
20.
Atmospheric reaction
26.
f = –x, f = –5m = –500cm; p =
28.
Being nearer to earth, there appear many points of sources of light
100
= –0.2 D
f
(480)
X-Science (E.M.)
29.
violet, red
Different colours having different wavelength bend through different angles while passing
through prism.
30.
size of particles and wavelengths of light
31.
Atmospheric refraction
32.
Smaller particles scatter light of shorter wavelength (blue) larger particles scatter light of
longer wavelength (e.g. red)
33.
opposite to sun; outside the arc
34.
red colour least scattered so it can be seen from maximum distance.
35.
light senstive cells take time to get activated
36.
one eye gives view of ∠150° whereas two eyes make it ∠180° . Better 3D view.
37.
Double convex lens; no change because eye lens adjust its focal length accodingly.
38.
x ′ = 1m = 100cm, d = 25cm, P = ?, f = ?
x ′d
x′ – d
f =
100 × 25
= 3.3D [Covex lens]
100 − 25
39.
x = 80cm, P = ?
f = –x = – 80cm
P=
100 100
=
= −1.25 D [Concave lens]
f
–80
Chapter - 12 Electricity
1.
Ampere
2.
Coulomb
3.
1 Coulumb = charge of 6x1018 electrons
4.
volt
5.
1. wire crossing without joining, 2. Battery
6.
ohm
7.
current in circuit become half
8.
wire of length 20cm
9.
same
(481)
X-Science (E.M.)
10.
(1) voltmeter, (2) ammeter
11.
Rheostat
12.
Variable – resistance
13.
(1) Voltmeter in parallel, (2) ammeter in series.
14.
Wire Q
15.
same
16.
Vα I
17.
Copper or aluminium
18.
Watt
20.
KWh
21.
Alloy of tin and lead
24.
Tungston
25.
1KWH = 3.6MJ
26.
Rubber, Glass
27.
28.
Insulator
29.
Copper
30.
Mercury
31.
Electric motor and electric fan
32.
Nitrogen
35.
(i) R/q
38.
1KW = 1000W = V x I, I = 4.54A
40.
40 volt
41.
Q. = I x C = 1.35 x 104C
42.
5C = 5 x 6 x 1018 electrons
43.
4 ohm
45.
32 x 10–8 ohm
48.
I = 18.18 amp; R = 121 ohm; 8kwh
49.
separate = 10amp, series = 5 amp. Parallel = 20amp
50.
Electric iron
52.
2 Ohm
53.
Rs. 576
1 ohm =
1 volt
1 Ampere
(ii) Same
(482)
X-Science (E.M.)
54
6
ohm
7
55.
0.83ohm
56.
4 resistors
57.
(i) In parallel Rmin =
10
ohms
3
(ii) In series, Rmax = 30 ohm
R min.
10
1
=
=
R max.
3×30
9
58.
(i) R = 10 ohm
(ii) I = 0.6A (iii) V = 4.2V
Chapter - 13 Magnetic effects of electric Current
2.
Increases
3.
North to south
4.
scalar quantities - Resistance, Electric power
5.
Decreases
7.
Oersted
8.
Strength of magnetic field
11.
Field lines
13.
Electromagnet
15.
Electric generator
16.
Solar cell, cell or battery
17.
Electric fan, washing machine
19.
50Hz
20.
A.C. (Alternating current)
21.
Direct Current (DC)
23.
Neutral – Black, live wire – Red.
25.
Direction
26.
live wire
27.
Electrical energy to mechanical energy
29.
Voltmeter, Ammeter
31.
Brain, Heart
32.
MRI
(Magnetic Resonance Imaging)
(483)
X-Science (E.M.)
34.
50Hz
35.
(i) North to south
(ii) South to North
45.
(i) Increases
(ii) Decreases
50.
Green
(iii) Increases
Chapter - 14 Sources of Energy
2.
Fossil Fuel
5.
Trapping of heat rays by CO2 gas.
6.
Acidic oxides obtained from burning of fossil fuel (oxides of carbons Nitrogen & sulphar)
causes acid rain.
9.
Animal (cow dung ) & plant product (wood)
10.
Methane
11.
Mixture of cow dung & water
12.
rich in nitrogen & phosphorous used as manure.
13.
Absorbs max. heat.
14.
Solar cell
18.
Hydrogen
20.
Silver
21.
Solar Cell
22.
Uranium
23.
Glass plate
24.
Solar cooker, Solar heater
26.
Silicon
28.
eg. water, wind
29.
e.g. - coal, petroleum
30.
renewable source - wind, tide
non renewable source - coal, petroleum, wood, natural gas
33.
Methane, CO2, H2 & H2S.
38.
Difference in sea level due to gravitational pull of moon on the spinning earth.
40.
Concave mirror.
41.
(i) by judicious use of non renewable sources
(ii) by using renewable sources
(484)
X-Science (E.M.)
Chapter - 15 Our Environment
1.
Recycling of different materials.
3.
Producers, consumers, decomposers
4.
Green plants, certain blue green algae
6.
CO2 and H2O
7.
Each organism generally eaten by two or more organisms.
8.
Secondary
9.
Accumulation of materials
10.
(i) Bacteria
12.
Skin cancer
15.
Grass to rabbit
17.
UNEP
22.
we lack enzymes to obtain coal’s energy
31.
I = 9000 KJ, V = 0.9 KJ
32.
Extinguisher or refregerant cause ozone layer depletion
35.
Neem in autotroph, Bread mold parasite
39.
Deer, grass hopper, scorpion
40.
owl, lion, vulture, fox
(ii) Fungi
Chapter - 16 Management of Natural Resources
1.
Everything that comes from nature and can be used. Coal, water, wind, petroleum
3.
Reduce
5.
Amrita Devi Bishnoi National Award for wild life conservation.
6.
Coliform
7.
Number of species found in an area.
8.
Deposits are reducing faster due to excessive use gases produced cause global warming
9.
Indira Gandhi Canal
10.
Irrigation, generating electricity
11.
Renivillage in Garhwal
12.
Carbon, nitrogen, hydrogen, sulphur
13.
CO2
14.
Sh. Sunder Lal Bahuguna
15.
To preserve biodiversity as a whole / loss of ecological stability.
16.
Loss of diverisity may lead to loss of ecological stability
Recycle
Reuse
(485)
X-Science (E.M.)
17.
Large amount of slag is discarded for every ton of metal extracted.
18.
Reuse, No energy is required
21.
Paper industries – bamboos, Bidi – Tendu leaves
22.
Devastation of forests, in balance of ecosystem, occurance of flood, droughts
24.
Fire wood timber, fruits
25.
employment, protection of forests
27.
Saving of sal forests of Arabari (Midnapore Distt )
29.
CO2 and H2O, Global warming, green house effect, Oxide of S, N – cause Acid Rain
30.
recharging of ground water, percolation. Khadins and nadis, bandharas and tals
31.
Reduce – less use of natural resourees
Recycle – recycle used items like plastic
Reuse – Use the same thing again
32.
Electricity, transport, industries
35.
Does not evaporate, provides moisture for vegetation, recharge wells, does not allow
mosquitoes to breed.
37.
Correct explanation. Benefits
(i) never evaporates
(ii) water spread out to recharge wells and provide moisture for vegetation
(iii) Does not provide breeding ground for mosquitoes
(iv) water is well protected from human and animal waste contamination.
(486)
X-Science (E.M.)
Set 1 (Solved)
BLUE PRINT
Sample Question Paper
Class - X – Science (Theory)
Form of
Questions
VAS
SA-1
SA-II
LA
(1 mark)
(2 marks)
(3 marks)
(5 marks)
Chemical Substances
3(3)
4(2)
6(2)
5(1)
18(8)
World of Living
2(2)
6(3)
3(1)
5(1)
16(7)
Effetcs of current
1(1)
4(2)
–
5(1)
10(4)
Light
2(2)
–
6(2)
–
8(4)
Natural Resources
1(1)
4(2)
3(1)
–
8(4)
Total
9(9)
18(9)
18(6)
15(3)
60(27)
Unit
(487)
Total
X-Science (E.M.)
Sample Question Paper (Solved)
Science
Class – X
Time Allowed : 2½ hours
Maximum Marks : 60
General Instructions :–
(i)
The questions paper comprises of two sections A and B. You are to attempt both
the sections.
(ii)
All questions are compulsory.
(iii)
There is no overall choice. However, internal choice has been provided in all the
three sections of 5 marks category. Only one option in such questions is to be
attempted.
(iv)
All questions of Section A and all questions of Section B are to be attempted
saperately.
(v)
Questions 1 to 6 and Section A and 17 to 19 in Section B are short questions.
These questions carry one mark each.
(vi)
Questions 7 to 10 in Section A and 20 to 24 in Section B are short answer type
questions and carry two marks each.
(vii)
Questions 11 to 14 in Section A and 25 to 26 in Section B are also short answer
type questions and carry three marks each.
(viii)
Questions 15 and 16 in Section A and 27 in Section B are long answer type
questions and carry five marks each.
Section – A
(Physics and Chemistry)
Q. 1
Write the equation for the process by which unsaturated vegetable oils are converted
into saturated fats?
Q. 2
Why does an aqueous solution of an acid conduct electricity?
Q. 3
Write the equation for the reaction of iron with steam.
Q. 4
Speed of light in water is 2.25 x 108 m/s and speed of light in vaccum is 3 x 108m/s.
Calculate the referactive index of water.
Q. 5
A ray of light AM incident on a spherical
mirror as shown in figure
Complete the figure.
A
M
C
(488)
F
P
X-Science (E.M.)
Q. 6
Define potential difference and write its S.I. unit.
Q. 7
What is displacement reaction? Identify the displaced substance from the following
reaction.
Zn( s) + CuSO4 (aq) → ZnSO4 (aq) + Cu ( s )
Q. 8
The atomic number of three elements X, Y and Z are 3, 5 and 13 respectively.
(i) which two elements belongs to the same period?
(ii) which two elements belong to the same group?
Q. 9
State Ohm’s law and write its mathematical representation.
Q. 10 An electric refrigerator rated 600W operates 5 hour per day. What is the cost of energy
to operate it for 20 days at rate of Rs. 5 per kilo watt.
Q. 11 How is plaster of paris chemically different from gypsum? How they can be
interconverted?
Q. 12 Give reasons for the following :–
(a) Zinc oxide is considered as an atmospheric oxide.
(b) Non metals generally do not displace hydrogen from dilute acid.
(c) Metals conduct electricity.
Q. 13 What is hypermetropia? What are the main causes of hypermetropia? How is its
corrected? Draw diagram.
Q. 14 An objects is placed in front of convex lens between focus and optical centre. Draw ray
diagram and state the nature, size and position of image.
Q. 15 (i) How ethanoic acid reacts with (a) sodium bicarbonate and (b) with sodium hydroxide.
(ii) Explain esterification with suitable reaction.
(iii) What are the end products of the combustion of a saturated hydrocarbon.
OR
(i) Define isomerism
(ii) Write the structural formula of two isomers of butane.
(iii) Draw the structure of cyclopentane.
(iv) Why does hard water form scum with soap?
Q. 16 (a) What is electromagnetic induction?
(b) Name the device which works on the principles of electromagnetic induction.
(c) Design an experiment to show the phenomenon of electromagnetic induction with
diagram.
OR
(489)
X-Science (E.M.)
(a) What is solenoid?
(b) Draw the diagram of magnetic field through and around a current carrying solenoid.
(c) How electromagnet is formed by solenoid?
Section – B
Q. 17 Name any one fish fossil.
Q. 18 Which nutrient of food is associated to muscular action?
Q. 19 Wind speed at a place is mostly around 12km/hr. Will you suggest to install a wind
energy farm here?
Q. 20 Define acquired traits? Give example.
Q. 21 Enlist one advantage and one disadvatnage of chemical communication in living
organism.
Q. 22 Write two changes brought about by testosterone.
Q. 23 A mango tree is a producer but not the bread mould. Give reasons.
Q. 24 Cite any two instances of community participation in forest management.
Q. 25 (i) Write two major limitations of using solar energy.
(ii) Which element is used to connect the solar cells in the solar panel.
Q. 26 Write three major steps of photosynthesis.
Q. 27 (i) Enumerate three major differences between aerobic and anaeribic
respiration.
(3)
(ii) Why rings of cartilage are present in trachea.
(1)
(iii) Write one functions of hairs inside the nasal cavity.
(1)
OR
(i) Describe the urine formation in human beings.
(2)
(ii) Draw a neat labelled diagram of nephron.
(3)
(490)
X-Science (E.M.)
Sample Question Paper
Science (SOLUTIONS)
Class – X
Section – A
R
A. 1
H H
R
Nickel Catalyst
C =C
R−C −C − R
R
R
R
(1 mark)
R
A. 2
because it produces H+ (hydrogen ion) in the solution
(1 mark)
A. 3
3Fe( s ) + 4 H 2O( g ) → Fe3O4 ( s ) + 4 H 2 ( g )
(1 mark)
A. 4
3 × 108
= 1.33
Referactive index of water =
2.25 × 108
P
M
A. 5
C
F
P
A. 6
Correct definition S.I. unit volt.
A. 7
A reaction in which, 9 more reactive elements displaced other
element from its solution.
Cu is displaced
A. 8
(i) X and Y
A. 9
Correct statement,
(1+1 mark)
(ii) Y and Z
(1+1 mark)
V
=R
I
(1+1 mark)
A. 10 Energy consumed = 60KW, Total cost of energy = Rs. 300
(1+1 mark)
A. 11 POP is CaSO4.½H2O while gypsum is CaSO4.2H2O
1
1
393 K
CaSO4 .2 H 2O 
→ CaSO4 . H 2O + 1 H 2O
2
2
Gypsum
POP
1
1½ H 2 O
CaSO4 . H 2O 

→ CaSO4 .2 H 2O
Moisture
2
(1+1+1 mark)
(491)
X-Science (E.M.)
A. 12 (a) because zinc oxides shows both acidic as well as basic behaviour. (1 mark)
(b) non metals are general are electrons accptors. Therefore they can’t
supply electrons to H+ ions and hence cannot displace hydrogen
from dilute acids.
(1 mark)
(c) Metals can lose electrons readily and therefore have electrons
which are free to move. Therefore they conduct electricity.
A. 13 Correct definition of defect on page no. 190 (N.C.E.R.T.)
Causes :–
(1 mark)
(1+1+½+½)
1. Increase in the focal length of eye lens.
2. Decrease in the size of eye ball.
fig. no. 11.3, page no. 190 (N.C.E.R.T. Book)
A. 14 Diagram no. 10.17 (f) N.C.E.R.T. Book page no. 181
A. 15 (i)
(a) CH 3COOH + NaHCO3 → CH 3COONa + H 2O + CO2
(1½+½+½+½)
(2+2+1)
(b) CH 3COOH + NaOH → CH 3COONa + H 2O
Acid
CH 3 − COOH + CH 3 − CH 2 − OH 
→ CH 3 − C − O − CH 2 − CH 3 + H 2O
(ii)
O
( Easter )
(iii) CO2 + H 2O
OR
(a)
(i) Correct definition
(1+1+1+2)
(ii) Correct structure
(iii) Correct structure
(b) Mg+2 and Ca+2 ions which are present in hard water from an insoluble
substances which is called scum
A. 16 (a) Correct definition
(1)
(b) Generator
(1)
(c) Activity no. 13.8, Page no. 233, N.C.E.R.T. Book,
fig. no. 13.16, Page no. 234, N.C.E.R.T. Book.
(3)
OR
(a) Correct definition
(1)
(b) Fig. no. 13.10, page no. 229, N.C.E.R.T. Book
(3)
(c) by inserting a magnetic material or soft iron piece inside a solenoid coil.
(1)
(492)
X-Science (E.M.)
Section – B
A. 17 Knightia
A. 18 Protein
A. 19 No
A. 20 definition, weight changes or any other
(1+1)
A. 21 Advantage - Reach all parts
(1)
Disadvantage - very slow
(1)
A. 22 Sperm formation, cracking of voice, hair growth etc.
(1+1)
A. 23 Mango - Autotroph, directly use solar energy. Bread mould parasite,
can’t use solar energy directly.
(1+1)
A. 24 Arabari forest, West Bengal. Chipko Movement, Uttarakhan
(1+1)
A. 25 (i) Solar energy - cloudy day, any other.
(2+1)
(ii) silicon
A. 26 (i) light absorption
(1+1+1)
(ii) photolysis of water
(iii) reduction of CO2 to food.
A. 27 (i) Aerobic - definition, ATP-38, energy efficient, products formed
(1+1+1)
Anaerobic - definition, ATP-2, less efficient, products formed
(ii) stop trachea from collapsing.
(1)
(iii) prevent dust particles and other impure substance from moving
inside the respiratory tract.
(1)
OR
(i) description of filteration, selective reabsorption
(2)
(ii) diagram, two labelling
(2+1)
(493)
X-Science (E.M.)
Sample Question Paper (Unsolved)
Science Theory
Class – X
Time Allowed : 2½ hours
Maximum Marks : 60
General Instructions :–
(i)
The questions paper comprises of two sections A and B. You are to attempt both
the sections.
(ii)
All questions are compulsory.
(iii)
There is no overall choice. However, internal choice has been provided in all the
three sections of 5 marks category. Only one option in such questions is to be
attempted.
(iv)
All questions of Section A and all questions of Section B are to be attempted
saperately.
(v)
Questions 1 to 6 and Section A and 17 to 19 in Section B are short questions.
These questions carry one mark each.
(vi)
Questions 7 to 10 in Section A and 20 to 24 in Section B are short answer type
questions and carry two marks each.
(vii)
Questions 11 to 14 in Section A and 25 to 26 in Section B are also short answer
type questions and carry three marks each.
(viii)
Questions 15 and 16 in Section A and 27 in Section B are long answer type
questions and carry five marks each.
Section – A
Q. 1
Name a metal which can displace hydrogen from dilute acid and metal cannot
displace hydrogen from dilute acid.
(1)
Q. 2
Write the balanced chemical equation for the following chemical reaction.
(1)
Magnesium (s) + Hydrochloric acid → Magnesium chloride (aq) + Hydrogen (g)
Q. 3
What is catenation? Which of the following is belong to the same homologous
series?
(1)
C3H8, C3H6, C4H8, C4H6
Q. 4
Take down this figure into your
answer book and complete the
path of the ray.
(1)
(494)
X-Science (E.M.)
Q. 5
Why is resistance less in parallel combination of resistors?
(1)
Q. 6
Why is lead tin alloy used for making fuse?
(1)
Q. 7
Write the chemical formula of bleaching powder. How is it prepared?
For what purpose it is used in paper factories?
(2)
Q. 8
Give reasons :–
(2)
(i) Platinum, Gold and Silver are used to make jewellary.
(ii) Aluminium is highly reactive metal, yet it is use to make utensils for cooking.
Q. 9
Explain with the help of diagram why a pencil partially immeresed in water
appears to be bent at the water surface.
Q. 10 Why does the sun look reddish at the time of sunrise and sunset?
(2)
(2)
Q. 11 An organic compound ‘A’ with molecular formula C2H4O2 produces acidic
effervescence on addition with sodium hydrogen carbonate.
(i) Identify the organic compound ‘A’
(ii) Name the gas evolved
(iii) How will you test for the gas.
Q. 12 Complete the following reaction.
(3)
(3)
O( g ) →
(i) 3Fe( s) + H(2Steam
)
sunlight
→
(ii) 6CO2 + 12 H 2O(l ) 
chlorophyll
(iii) Ca(OH ) 2 + Cl2 →
Q. 13 (a) Light enters from air to glass having referactive index 1.5, What is the
speed of light in glass? The speed of light in vaccum is 3 x 108m/s
(b) What is hypermetropia? How is it corrected?
(c) Draw a diagram to show the formation of an image by corrected
hypermetropic eye.
Q. 14 (i) Define one ohm
(ii) The value of currect I flowing in a given resistor for the corresponding
values of potential difference V across the resistor are given below :–
I (amperes) 0.5
1.0
2.0
3.0
4.0
V (volts)
1.6
3.4
6.7
10.2 13.2
(495)
(1)
(1)
(1)
(1)
(1)
X-Science (E.M.)
(iii) Plot a graph between V and I and Calculate the resistance of that resistor. (1)
Q. 15 (a) What are two limitations of Mendleev’s periodic table?
(b) An element X(2, 8, 3) combines saperately with NO3–, SO42– and PO43–
radicals. Write the formula of three compounds so formed, to which group
of the periodic table does the element X belong? Will it form covalent
or ionic compound? Why, give reason.
OR
The position of certain elements in the periodic table are shown below :–
Group
1
2
3-12 13
14
15
16
17
18
Period
1
G
H
2
A
I
B
C
3
D
E
F
(5)
Using the above table answer the following questions :–
(a) Which element will form only covalent compound?
(b) Which element is non metal with valency 2?
(c) Which element is metal with valency 2?
(d) Out of HCF which has largest atomic size?
(e) Give name of the family to which HCF belongs.
Q. 16 (a)
(b)
(c)
(d)
What is an electromagnet?
List any of its two uses.
Draw a labelled diagram to show how an electromagnet is made?
What is the purpose of the soft iron core used in making an electromagnet?
OR
(a) What is the difference between the terms overloading and short circuiting?
(b) Why are coils of electric heater made of an alloy rather than a pure metal?
(c) What is the function of an earth wire? Why is it necessary to earth metallic
appliances?
Section – B
Q. 17 What is the role of amylase enzyme present in saliva in the digestion of
food?
(1)
Q. 18 Name the two gases other than CO2 that are given out during burning of
fossil fuel which causes acid rain.
(1)
(496)
X-Science (E.M.)
Q. 19 Malarial parasites divides into many daughter individuals simultaneously
through multiple fission. State an advantage the parasite get because this
type of reproduction.
(1)
Q. 20 State any two advantages of vegetative propogation.
(2)
Q. 21 How is ozone layer is formed in the atmosphere? What is the function of
this layer?
(2)
Q. 22 Draw a diagram of neuron. Label axon and dendrite only.
(2)
Q. 23 Write one feature which is common to each of the following pairs of terms /
organs.
(i) glycogen and starch
(ii) chlorophyll and haemoglobin
(iii) gills and lungs
(iv) artries and veins
Q. 24 Why is reuse of material is better then recycling for saving our environment?
(2)
(2)
Q. 25 Mention any three activities undertaken by man which may result in economical
benefit but have actually caused reduction of natural resources?
(3)
Q. 26 What role does sexual reproduction play in evolution?
(3)
Q. 27 (a) Describe different tropic movements with suitable examples.
(b) What do you meant by nastic movements.
OR
(a) Draw a sectional view of human heart and label on it.
(i) Aorta
(ii) Right ventrical (iii) pulmonary vein
(b) State the functions of following components of transport system :
(i) Blood
(ii) lymph
(3)
(2)
(497)
(3)
(2)
X-Science (E.M.)
PRACTICAL SKILLS ( Based on each experiment )
MULTIPLE CHOICE QUESTIONS
TIME : 1½ Hrs.
MARKS : 20
TOTAL NO. OF QUESTIONS : 30
Q. NO. (1 - 20) OF ½ MARKS EACH.
M.C.Q. based on class IX prac.: 10
Q. NO. (21 - 30) OF 1 MARKS EACH.
M.C.Q. based on class X prac. : 10
Experiment - 1 (IX)
To prepare :–
(a) a true solution of common salt; sugar and alum.
1.
2.
3.
4.
A true solution of common salt is prepared by dissolving
(a) Common salt in HCl
(b) Common salt in H2O
(c) Common salt in NaOH
(d) none of the above
A solution of egg albumin in water is
(a) a true solution
(b) a suspension
(c) a colloidal solution
(d) none of these
Identify the colloid from the following :–
(a) Water – sand
(b) Water – salt
(c) Water – sugar
(d) Water – soap
To prepare a colloidal situation of starch we should
(a) Add starch powder to boiling water and cool
(b) Add starch power to cold water and boil.
(c) Heat starch powder, add it to cold water and then bring to boil.
(d) Add a thin paste of starch to boiling water while stirring.
(498)
X-Science (E.M.)
5.
Identify and choose correct sequence.
(a) Beaker, conical flask, flat bottom flask
(b) Beaker, flat bottom flask, conical flask
(c) Conical flask, beaker, flat bottom flask
(d) Beaker, conical flask, Round bottom flask
6.
7.
8.
Which of the following is stable when allowed to stand undisturbed for some time :–
(a) sugar solution
(b) solution of starch in water
(c) Milk
(d) All of the above
The random Zig Zag motion of colloidal particle is called :–
(a) Tyndall effect
(b) Brownian movement
(c) Ultrafilteration
(d) Centrifugation
Which of the following is true for a mixture of (NH4)2CO3 in water?
STABILITY TRANSPARENCY FILTERABILITY
9.
a
stable
transparent
no residue
b
unstable
opaque
residue
c
stable
translucent
non residue
d
stable
translucent
residue
What is the correct description of a, b, c in the following
figure related to the preparation of a true solution.
(a) A = glass rod
B = beaker
C = Solution
(499)
X-Science (E.M.)
10.
11.
12.
(b) A = Beaker
B = glass rod
C = Solution
(c) A = glass rod
B = Solution
C = Beaker
(d) A = Beaker
B = Soltion
C = glass rod
Which of the following pass through filter paper unchanged :–
(a) A suspension
(b) True solution
(c) both (a) and (b)
(d) none of them
If no more solute dissolved in a given solvent at a given temperature, the solution is
said to be :–
(a) super saturated
(b) saturated
(c) unsaturated
(d) none of the above
The following substances are added to water in a beaker as shown below. The mixture
is stirred well. A true solution is found in the beaker.
(a) I
13.
(b) II
(c) III
(d) IV
In a suspension the particles :–
(a) are visible
(b) remain suspended in solution
(c) remain suspended then settle down
(d) float
(500)
X-Science (E.M.)
Experiment - 2 (IX)
TO PREPARE MIXTURE AND COMPOUNDS
AIM :– To prepare (a) Mixture
(b) Compound using iron filings and sulpher powder
(a) Appearance
(b) Behaviour towards magnet
(c) Behaviour towards CS2
(d) Effect of heat
1.
2.
3.
4.
5.
Which one of the following is a mixture of two elements?
(a) Iron filings + Sulphur powder
(b) Sugar + commom salt
(c) Water + milk
(d) Air
To prepare iron sulphide by heating a mixture of iron filings and sulphur powder, we
should use a :–
(a) Copper dish
(b) Watch glass
(c) China dish
(d) Petri dish
When a mixture of iron filings and sulphur is strongly heated in a china dish the colour
of product obtained is :–
(a) Grey
(b) Orange
(c) Black
(d) Pale yellow
Sulphur is insoluble in :–
(a) H2O
(b) CS2
(c) HNO3
(d) both (a) and (c)
Which symbol represents “FLAMMABLE”
(a)
(b)
(501)
X-Science (E.M.)
(c)
6.
(d)
Observe the following figure. What is the correct description of A.B.C. in the following
figures related with heating of a substance.
(a) A = Test tube, B = Burner, C = Test tube holder
(b) A = Test tube holder, B = Burner, C = Test tube
(c) A = Test tube holder, B = Test tube, C = Burner
(d) A = Test tube, B = Test tube holder, C = Burner
7.
Mixture is :
(a) always homogenous
(b) always heterogenous
(c) either homogenous or heterogenous(d) none of these
8.
Out of the following which one is not the property of mixture.
(a) It is hetrogenous
(b) it is a sulphur of variable composition
(c) it is a system of constant composition
(d) its component cannot be separated by physical method
9.
Which one is the correct method of separating iron filings from sulphur powder?
(a) Heating in a boiling tube
(b) Heating with water
(502)
X-Science (E.M.)
(c) Moving a magnet through the mixture
(d) Heating in a China dish
10.
11.
Which one is the mixture of an element and a compound.
(a) Common salt + sugar
(b) oil + water
(c) Air
(d) Sulphur + Carbondisulphide
On mixing the compound iron sulphide in carbondisulphide the change occur is
(a) yellow particles of sulphur will dissolve
(b) grey particles or iron sulphide will dissolve
(c) both iron and sulphur particle will dissolve
(d) none of these will occur
(503)
X-Science (E.M.)
Experiment - 3 (IX)
CHEMICAL REACTION
1.
2.
3.
4.
5.
Which one of the following is a direct combination reaction?
(a) Burning Mg in air to give MgO
(b) Heating iron and sulphur
(c) Burning sodium in a current of chlorine
(d) Each one
Which one is a combination reaction between two elements?
(a) O2 + 2CO → 2CO2
(b) HCl + NH 3 → NH 4Cl
(c) N 2 + 3H 2 → 2 NH 3
(d) CaO + CO2 → CaCO3
Burning of magnesium is oxygen forms the compound
(a) Magnesium chloride
(b) Magnesium iodide
(c) Magnesium oxide
(d) none of the above
Which one is a combination reaction between two compounds?
(a) 2CO + O2 → 2CO2
(b) HCl + NH 3 → NH 4Cl
(c) N 2 + 3H 2 → 2 NH 3
(d) C + CO2 → 2CO
Which one is the correct statement about the reaction?
AgNO3( ag ) + NaCl( aq ) → AgCl( s ) ↓ + NaNO3( aq )
6.
(a) Combination
(b) Displacement reaction
(c) Double displacement reaction
(d) Decomposition reaction
The reaction between iron and copper sulphate in water represents which type of reaction?
(a) Decomposition
(b) Direct combination
(c) Single displacement
(d) Double decomposition
(504)
X-Science (E.M.)
7.
8.
When blue litmus is added to water extract of MgO
(a) It turns red
(b) it becomes colourless
(c) it turns green
(d) no change observed
Which one is the correct statement about the reaction.
Fe( s) + CuSO4 (aq) → FeSO4 (aq) + Cu ( s)?
(a) It is a single dispalcement reaction
(b) In this reaction Fe is oxidised and Cu 2 + is reduced
(c) Fe is a reducing agent and Cu 2 + is an oxidizing agent.
(d) All of the above.
9.
10.
The insoluble product (precipitate) is formed when Barium Chloride solution is mixed
with sodium sulphate solution. Identify the compound formed as white precipitate.
(a) barium sulphite
(b) barium sulphide
(c) barium sulphate
(d) none of these
Name gas G in the following figure. (Figure for the reaction between zinc and sulphuric
acid)
Conical flask
(a) SO2
11.
12.
(b) H2
(c) CO2
(d) O2
What are the products formed when zinc reacts with dilute sulphuric acid :–
(a) ZnSO4 + H2
(b) ZnS + H2
(c) ZnSO4 + H2O
(d) ZnO + SO2
What is (s) in the given figure for the reaction?
(a) Magnesium nitride
(b) Magnesium sulphide
(505)
X-Science (E.M.)
(c) Magnesium chloride
(d) Magnesium oxide
13.
On burning magnesium ribbon in air it is observed that :–
(a) A greenish gas is obtained
(b) It burns out brightly giving out a golden colour
(c) It burns brightly leaving a blue ash
(d) It burns brightly, leaving behind white powder
14.
Take dilute sulphuric acid in a test and put a few zinc granules into the test tube. You
would observe that :–
(a) zinc granules change to powder
(b) colour of zinc changes from grey to white
(c) The size of zinc granules keep decreasing
(d) the surface of zinc metal becomes bright
15.
When dilute sulphuric acid is added to zinc granules, it is observed that
(a) a precipitate is formed
(b) the reaction mixture turns yellow
(c) the container beomes hot
(d) bubbles starts coming out from the surface of zinc granules.
16.
The safest method to detect hydrogen gas produced in a reaction would be the method
shown in :–
Zn+dil.
H2SO4
(a)
Zn+dil.
H2SO4
Zn+dil.
H2SO4
(b)
(c)
(506)
Zn+dil.
H2SO4
(d)
X-Science (E.M.)
17.
18.
19
20.
21.
22.
(a)
(b)
(c)
(d)
Colour of lead nitrate is
(a) Red
(b) Blue
(c) White
(d) Yellow
The products formed by heating of lead nitrate are :–
(a) PbO2, NO2
(b) PbO, NO2, O2
(c) PbO2, NO
(d) PbO, NO, O3
Lead nitrate is :–
(a) insoluble in water
(b) soluble in water
(c) partially soluble in water
(d) remain floating on water surface
Lead nitrate is :–
(a) A reducing agent
(b) An oxidising agent
(c) A catalyst
(d) None of these
When lead nitrate is heated in a test tube, colour of the rsidue is :–
(a) Pale green
(b) Red
(c) White
(d) Blue
Heat
2 Pb( NO3 ) 2 
→ 2 PbO + 4 NO2 + O2 is an example of :–
(a) thermal decomposition
(b) catalytic decomposition
(c) combination reaction
(d) displacement reaction
(507)
X-Science (E.M.)
Experiment - 4 (IX)
AIM :–To verify laws of reflection of sound.
1.
2.
Sound wave can travel
(a) in vacuum only
(b) in vacuum as well as in a material medium
(c) in a material medium only
(d) neither in vacuum not in material medium
Sound travels in air at a speed of 332 m/s. It means that
(a) air moves with a speed of 332 ms–1.
(b) air does not move forward with the sound wave but the disturbance moves with
this speed.
(c) sound moves with the speed of 332ms–1
(d) the listener moves with a speed of 332m–1
3.
4.
5.
6.
When a sound is allowed to fall normally on the reflecting surface, the angle at which
the intensity of sound be maximum is :–
(a) 60°
(b) 0°
(c) 30°
(d) 90°
Sound is a form of
(a) matter
(b) energy
(c) smell
(d) sensation of warmth
Sound waves cannot pass through
(a) air
(b) helium gas
(c) iron
(d) vacuum
If air in the room warms up, the speed of sound in it
(a) increases
(b) remains the same
(c) decreases
(d) fluctuates
(508)
X-Science (E.M.)
7.
8.
The astronauts on the moon can see each other but cannot hear each other’s voice,
because
(a) moon is far off from earth
(b) temperature variation is at large
(c) there is no light
(d) there is no atmosphere
While doing experiment on verifying the law of reflection of sound, four students
measureed the angles ∠i and ∠r as shown in the diagram :–
i
i
r
r
r
i
r
i
The correct measurement of the angle of incidence and angle of reflection, has been
done by the student.
9.
10.
(a) A
(b) B
(c) C
(d) D
In which medium would you be able to hear the sound in the experiment?
(a) From the air
(b) From the metal tube
(c) From the wooden plank
(d) Both (a) and (b)
The sound received in the ears while doing the experiment should be
(a) the direct sound from the clock
(b) the sound reflected from any reflecting surface
(c) the sound coming through the tube after reflection
(d) any of these
11.
The mininmum time gap between the two sounds to be heard distinctly must be
(a) 0.1 second
(b) 0.15 second
(c) 2.0 second
(d) 2.5 second
(509)
X-Science (E.M.)
12.
Reflection of sound obeys the law
(a) angle of incidence > angle of reflection
(b) angle of incidence < angle of reflection
(c) angle of incidence = angle of reflection
(d) angle of incidence has no relationship with angle of reflection
13.
14.
The correct position of the ear of the observer is shown in :–
(a) Fig. A
(b) Fig. B
(c) Fig. C
(d) Fig. D
The physical quantity that will remain invarient after reflection is :–
(a) velocity
(b) wavelength
(c) frequency
(d) all of these
(510)
X-Science (E.M.)
Experiment - 5 (IX)
Density of Solid (denser than water)
AIM :–To determine the density of solid (denser then water) by using a spring balance
and a measuring cylinder.
1.
2.
3.
4.
5.
Relative density of any liquid is calculate with respect to
(a) Alcohol
(b) Glycerine
(c) Water
(d) All of these
S.I. unit of relative density is
(a) kg/m³
(b) g/m³
(c) No unit
(d) none of these
Archimedes principle is valid for
(a) solid and liquid
(b) gas and solid
(c) liquid and gas
(d) none of these
In an experiment, to find the density of a solid, the device by which volume of a solid
can be measured by taking water in it, is :–
(a) beaker
(b) conical flask
(c) measuring cylinder
(d) round bottom flask
The least count of the spring balance shown below is :–
(a) 5g
(b) 2g
(c) 1g
(d) 0.5g
(511)
X-Science (E.M.)
6.
A solid body is suspended from a hook of the
spring balance as shown in fig. Dazy noted the
reading. Which of the following is correct :–
(a) 8g
(b) 16g
(c) 14g
(d) 18g
7.
8.
If the object used in experiment is dipped partly
in liquid (density of object is less then liquid)
then the formula from which density of liquid is
calculated as :–
(a)
Weight of Solid
Volume of Solid
(b)
Weight loss in Solid
Volume of liquid displaced
(c)
Weight of liquid displaced
Volume of Solid
(d)
Mass of Solid
Volume of liquid displaced by Solid
The correct experimental setup to find out the volume of solid is :–
(a) A
(b) B
(c) C
(d) D
(512)
X-Science (E.M.)
9.
10.
Which of the following container should be more appropriate for determination of density
of a piece of stone?
(a) A
(b) B
(c) C
(d) D
Three students A, B and C noted the water level
reading in the measuring cylinder as shown in
fig. The correct way of taking reading will be of
student :–
(a) only A
(b) only B
(c) only C
(d) both A and B
11.
A stone of mass 66g is tide to a fine
cotton thread and then immeresed in
water contained in a measuring cylinder.
The density of stone is :–
(a) 25 g/mL
(b) 90 g/mL
(c) 6 g/mL
(d) 40 g/mL
12.
The volume of liquid filled in the graduated cylinder is :–
(a) 50.2ml
(b) 50.4ml
(c) 52ml
(d) 54ml
(513)
X-Science (E.M.)
Experiment - 6 (IX)
AIM :–To establish the relation between the loss in weight of solid when fully immersed
in (a) tap water, (b) strongly salty water with the weight of liquid displaced by it by taking
at least two different solids.
1.
2.
3.
4.
Of the density of the object placed in a liquid is equal to the density of the liquid, the
object will
(a) sink
(b) float wholly immersed
(c) float
(d) float completely above
the liquid
Adding salt to water will
(a) Increase its density
(b) decrease its density
(c) not effect its density
(d) sometimes increase, sometimes decrease
In which case the loss in weight is more
(a) Salted water
(b) Tap water
(c) Same in both
(d) Double in salt water then tap water
In the experiment to establish the relation between loss of weight of an immersed solid
with the weight of water displaced by it, the correct set up is shown in figure.
(a) A
(b) B
(c) C
(d) D
(514)
X-Science (E.M.)
5.
The water level in a measuring cylinder, before and after immersing a solid in it, is
shown in the figure. The volume of the given solid in, cc, is.....
(a) 1.8
6.
(b) 2.0
(c) 2.2
(d) 2.4
Four measuring cylinders with different least counts are shown in figure A, B, C and D.
The most suitable cylinder for determining the volume of a cube of side nearly 1cm is
......
(a) A
(b) B
(c) C
(515)
(d) D
X-Science (E.M.)
7.
The correct way of measuring volume using a graduated cylinder is shown in
A
(a) A
8.
B
(b) B
C
(c) C
D
(d) D
The spring balance shown here is used to measure the weight of a given solid. The
weight of the solid is.
(a) 115g wt
(b) 118g wt
(c) 120g wt
(d) 125g wt
9.
The weight of a solid iron cube of side 4cm is to be
determined. Of the four spring balances available, the
one best suited for this purpose would have
(a) range = 0 to 100g.wt., and least count = 1g.wt.
(b) range = 0 to 100g.wt., and least count = 5g.wt.
(c) range = 0 to 1000g.wt., and least count = 10g.wt.
(d) range = 0 to 1000g.wt., and least count = 25g.wt.
(516)
X-Science (E.M.)
10.
11.
Two bodies of equal volume on (A) is rock salt and (B) is made up of chalk are immersed
to strongly salty water.
(a) A will sink, B will also sink
(b) A will float, B will sink
(c) Depends on the density of body
(d) Both float irrespective of volume of strongly
salty water.
In the experiment to establish the relation between loss in weight of an immersed solid
body with a weight of water displaced by it, a student start lowering the solid body
gradually in water, he observe the reading of spring balance and find it.
(a) decreases as the solid body is gradually lowered in water
(b) increases as the solid body is gradually lowered in waetr
(c) no change
(d) first decreases then increases
12.
A given solid is weighed in air using a spring balance. It is then weighed by immersing
it fully, in each of the three vessels containing water, as shown. Its weight then immersed,
will be
A
B
C
(a) least in vessel C
(b) least in vessel B
(c) least in vessel A
(d) equal in all the three vessels
(517)
X-Science (E.M.)
Experiment - 7 (IX)
AIM :–To measure temperature of hot water as it cools and plot a temperature time
graph.
1.
2.
The temperature time graph obtained when a hot liquid is allowed to cool, is likely to
resemble graph.
(a) A
(b) B
(c) C
(d) D
Of the four experimental set ups shown here to study temperature time graph, the best
one is
A
3.
B
C
(a) A
(b) B
(c) C
(d) D
D
Which of the following is not a precaution of this experiment?
(a) The electric fan should be switched off.
(b) While plotting the graph, time should be plotted along the y-axis and temperature
along the x-axis.
(518)
X-Science (E.M.)
(c) Keep stirring the hot water in the caloriemeter / beaker.
(d) The thermometer bulb should be dipped inside the water in the beaker.
4.
It is necessary to stir the hot water in the beaker in order to
(a) increase the temperature of water.
(b) gain heat
(c) lower the temperature of water
(d) keep the loss of heat uniform
5.
Slope of time temperature graph is a measure of
(a) loss of energy
(b) rate of loss of energy
(c) energy required to change the state (d) energy required to maintain a state
6.
The rate of cooling of a liquid depends on
(a) specific heat of the liquid
(b) the difference between the temperature of the liquid and the surroundings
(c) area of liquid surface exposed to the surroundings
(d) rate of fall of temperature of the liquid.
7.
The temperature time variation graphs, as obtained by four students A, B, C and D are
as shown. The graph, likely to be correct as that of student.
(a) A
(b) B
(c) C
(519)
(d) D
X-Science (E.M.)
8.
9.
Instrument used to measue the temperature
(a) Lactometer
(b) Thermometer
(c) Barometer
(d) None of these
Which of the following is correct way of studying the cooling of water?
(a) A
10.
(b) B
(c) C
(d) D
Water is chosen for studying cooling of liquids because
(a) it has a convinient temperature range
(b) it cools quickly
(c) it is liquid
(d) it is the only chemical in nature with
specific properties.
(520)
X-Science (E.M.)
Experiment - 8 (IX)
AIM :–To determine the velocity of a pulse propogated through a stretched spring.
1.
2.
3.
4.
5.
Waves which propagates in a slinky are
(a) mechanical
(b) Gravitational
(c) Magnetic
(d) Light
Select the right option : Sound waves are
(a) Longitudinal waves
(b) Transverse waves
(c) Electromagnetic waves
(d) None of these
Velocity of which physical quantity can be measured by the pulse propagation in the
slinky.
(a) Mechanical waves
(b) Sound
(c) Heat
(d) Electromagnetic waves
Two equal weights are attatched with a slinky and a wire. The velocity of the pulse
produced is slinky in comparison to wire will be
(a) different at different positions
(b) more
(c) less
(d) comparison is not possible
If a pulse hits at the fixed end as shown below, the best shown reflected pulse is
(a)
(b)
(c)
(d)
(521)
X-Science (E.M.)
6.
7.
8.
Palak was calculating the velocity of wave using a slinky. He asked his teacher regarding
the features of spring to be used. The teacher replied that the spring should be
(a) long, soft and flexible
(b) shorter, soft and flexible
(c) shorter, hard and flexible
(d) long, soft but not flexible
The physical quantity that will remain invariant after reflection is
(a) velocity
(b) wave length
(c) freqency
(d) all of the above
We can sense a compression in a spring if
(a) turns are close together
(b) neither close nor apart
(c) turns are further apart than normal (d) none of these
9.
10.
11.
In a wave motion in string, every particle
(a) does not displace at all
(b) does not oscillate
(c) oscillates
(d) Displaces from one end to the other end
The speed of propagation of a pulse in a slinky spring does not depends upon
(a) material of slinky
(b) room temperature
(c) length of slinky
(d) all of these
In the experiment for determining the velocity of propagation of a pulse in a slinky, we
prefer a long slinky :
(a) because pulse cannot be formed in a short slinky
(b) so that the time taken by pulse to move from one end of slinky to another in more
(c) so that pulse may move through it easily.
(d) none of these
12.
Relation between velocity V, wave length λ and frequency
(a) λ = Vn
(c) V =
λ
n
(b) V = n × λ
(d) n = λ × V
(522)
X-Science (E.M.)
Experiment - 9 (IX)
AIM :–To prepare stained temporary mount of onion peel to record observations and
draw labelled diagram.
1.
Which one of the following is the correct step, in the procedure for making a temporary
slide of human cheek cell.
(a) place the cheek cells scrapings in the watch glass containing water.
(b) place the cheek cells scrapings in the centre of a clean side.
(c) dip the toothpick, containing cheek cell scrapings, in the stain and then transfer to a
clean side.
(d) obtain cheek cells, directly on the slide, using its edge to scrap the inside of the
cheek.
2.
A frehsly prepared slide of onion peel was viewed under a compound microscope. It was
noticed that when the cells of one end were focussed, the cells of other becomes out of
focus and vice versa. Choose the reason for this observation.
(a) Uniform light was not coming through the diaphragm.
(b) The peel was not uniformly spread on the slide.
(c) The peel was overstained.
(d) The magnification of eye piece was very low.
3.
In a temporary mount of cheek cells, methylene blue would stain
(a) Nucleus only
(b) cell membrane and mitochondria
(c) chloroplast and mitochondria
(d) chloroplast only
4.
The power of objective lens is 10x and that of eyepiece of 10x, then the total magnification
of obtained will be
(a) 20x
(b) 1x
(c) 1010x
(d) 100x
(523)
X-Science (E.M.)
5.
Identify the typical cheek cell from the following
Cell menbrane
Cytoplasm
(a)
Nucleus
(b)
Vacuole
Cheek wall
Cell menbrane
Cell wall
(c)
Nucleus
(d)
7.
8.
9.
10.
Nucleus
Cytoplasm
Vacuole
6.
Nucleus
Which of the following cell organelle constituents can be seen under microscope while
observing human cheek cells.
(a) Chloroplast
(b) Mitochondria
(c) Nucleus
(d) Nucleolus
Vacuoles are big in size and less in numbers in
(a) plant cells
(b) animals cells
(c) both of these
(d) none of these
We put the coverslip on the slide very gently to
(a) avoid the crushing of the material
(b) avoid oozing of glycerin and stain
(c) avoid the entry of air bubbles
(d) none of these
Pick the odd one out :–
(a) big vacuoles
(b) plastids
(c) cell wall
(d) centrioles
Which one is present nearest to plasma membrane in plant cell?
(a) primary cell wall
(b) secondary cell wall
(c) middle lamella
(d) tonoplast
(524)
X-Science (E.M.)
11.
Deepali observed a slide of human cheek cells under the microscope in its (i) low
magnifying power, (ii) high magnifying power settings. In the first setting she has
observed :
(a) more cells in a darker field of view
(b) fewer cells in a darker field of view
(c) more cells in a brighter field of view
(d) fewer cells in a brighter field of view
12.
Temporary mount of a tissue is made in
(a) Wax
(b) Canada Balsam
(c) Alcohol
(d) Glycerine
(525)
X-Science (E.M.)
Experiment - 10 (IX)
AIM :–To identify parenchyma and sclerenchyma tissues in plant and striped muscle
fibre and nerve cell in animals from prepared slides and to draw their labelled diagrams.
1.
Identify the collenchyma tissue from the following :–
A
2.
3.
B
C
(a) A
(b) B
(c) C
(d) C and B
Major function of scherenchyma is
(a) photosynthesis
(b) photorespiration
(c) providing buoyancy in water
(d) providing mechanical strength
Identify the wrongly labelled from the following diagram of parenchyma cells.
(a) Nucleus
(b) Intercellular space
(c) Cell wall
(d) Vacuole
4.
Label ‘A’ and ‘B’ correctly
(a) A – Nucleus, B – Dendrite
(b) A – Dendrite, B – Axon
(c) A – Axon, B – Dendrite
(d) A – Dendrite, B – Nucleus
(526)
X-Science (E.M.)
5.
6.
Sclerenchymatous tissue should be stained with
(a) Crystall violet
(b) Methyl orange
(c) Methylene blue
(d) Safranine
The tissue that conducts impulses in animals is
(a) nervous
7.
(c) muscular
(d) meristematic
The number of nuleus in striated muscle is
(a) two
8.
(b) epithelial
(b) many
(c) four
(d) one
You are observing a prepared slide of striped muscle fibres from cockroach’s leg. When
you focus the microscope, the striations appear pale and indistinct. To make the striations
clearly visible, you would
(a) slowly close the diaphragm to reduce the light
(b) remove the mirror to cut out light
(c) change the eye piece to increase magnification
(d) replace the objective to decrease magnification
9.
10.
11.
Which of the following is a simple tissue
(a) parenchyma
(b) xylem
(c) phloem
(d) none of these
A permanent slide of nerve cell placed under microscope is not in perfect focus. To
obtain its sharp image, we should adjust :–
(a) slide on the stage
(b) eye piece
(c) Coarse and fine adjustment
(d) mirror
Four students (A–D), independently
observed parenchyma under the
microscope and label the parts, marked
I, II, III, IV, V, as per the record given
below :–
(527)
X-Science (E.M.)
Student
I
II
III
IV
V
A
Cell membrane
Nucleus
Cell wall
Vacuole
Cytoplasm
B
Cytoplasm
Cell Membrane
Vacuole
Cell wall
Nucleus
C
Vacuole
Cell wall
D
Cell wall
inter cellular
space
Nucleus Cell membrane Cytoplasm
Nucleus
Cytoplasm
Vacuole
The labelling has been done correctly by student
12.
(a) A
(b) B
(c) C
(d) D
Observe and identify the tissue in following diagrams. Choose the correct sequence.
(a) Sclerenchyma – Parenchyma – Onion peel – cheek wall
(b) Parenchyma – Sclerenchyma – Onion peel – cheek wall
(c) Parenchyma – Sclerenchyma – cheek wall – Onion peel
(d) Sclerenchyma – Parenchyma – cheek wall – Onion peel
(528)
X-Science (E.M.)
Experiment - 11 (IX)
AIM :–To saperate the components of the mixture of sand, common salt and ammonium
chloride (or camphor) by sublimation.
1.
Pure substance exhibits the proportion
(a) it should have a fixed melting and boiling point.
(b) it should have definite specific gravity
(c) All its parts should have uniform composition
(d) all the three
2.
Sublimation is the process in which on heating
(a) a liquid changes into solid
(b) a solid changes into liquid and then changes into gas
(c) a solid changes into gas directly
(d) none of these
3.
The principle of separation of the substance is based on
(a) the change of solid into liquid
(b) the similarities of the substances
(c) the differences in the properties of the substances
(d) none of the above
4.
The distillation in the process of heating
(a) a solid to change into liquid & vice versa
(b) a liquid to change into gas and vice versa
(c) a solid to change into gas and vice versa
(d) none of the above
5.
A student by mistake mixed iron filings and sulphur powder. He wants to separate them
from each other. The method you would advice him to dissolve the mixture is
(529)
X-Science (E.M.)
(a) boiling water
(b) cold water
(c) carbon disulphate
6.
7.
8.
(d) kerosene
In the given figure, identify the place at which you can find only pure ammonium chloride
(NH4Cl) after heating
(a) B
(b) C
(c) A
(d) A & B both
The aqueous mixture of salt and sand can be separated by the following method.
(a) filteration
(b) sublimation
(c) condensation
(d) melting
Sublimation is used to separate
(a) two liquids having different boiling points
(b) two liquids having same melting points
(c) volatile and non volatile solids
(d) volatile solids having same melting points
9.
heat
Which one of the following figure describes the processing sublimation solid →
vapours?
(530)
X-Science (E.M.)
10.
(a) A
(b) B
(c) C
(d) D
When sodium chloride and ammonium chloride are dissolved in water and filtered, the
residue is :–
(a) Sodium chloride
(b) Ammonium chloride
(c) Both
(d) None
(531)
X-Science (E.M.)
Experiment - 12 (IX)
AIM :– To determine the melting point of ice and boiling point of water
1.
The melting point of ice under normal pressure is
(a) 0°C
2.
3.
5.
6.
7.
(c) 100°C
(d) none of these
The process in which a solid on heating changes into a liquid is called
(a) freezing
(b) expansion
(c) melting
(d) contraction
The boiling point of pure water under standard atmospheric pressure is
(a) 373k
4.
(b) 37°C
(b) 273k
(c) 0k
(c) 100k
The process in which a liquid changes into its gases state at temperature below its
boiling point is called
(a) Boiling
(b) Evaporation
(c) Cooling
(d) Condensation
When ice melt, its temperature
(a) remains constant
(b) increase
(c) decrease
(d) changes
In the determination of melting point of ice correct, reading in the thermometer is noted
when :–
(a) temperature starts rising
(b) temperature becomes constant
(c) ice starts melting
(d) whole of the ice gets melted
Which one of the following should be selected for determination of boiling point of water
more accurately.
(a) Distilled water
(b) Tap water
(c) Salty water
(d) Rain water
(532)
X-Science (E.M.)
8.
9.
10.
While determining the boiling point of water more accurately, the bulb of thermometer
should :–
(a) dip in water
(b) keep just above the surface
(c) touch the bottom of container
(d) near the cork of the container
Which one of the following should be selected for determination of melting point of ice
more accurately.
(a) ice mixed with salt
(b) ice made from tap water
(c) ice made from distilled water
(d) ice made from rain water
Which one of the following is the most appropriate set up to determine the boiling point
of water.
I
II
III
(a) I
(b) II
(c) III
(d) IV
(533)
IV
X-Science (E.M.)
Experiment - 13 (IX)
AIM :– (a) To test the presence of starch in the given food sample.
(b) To test the presence of adulterant metanil yellow in dal.
1.
2.
3.
4.
5.
6.
ISI stands for
(a) Indian School Institute
(b) Indian Space Institute
(c) International Standard Institute
(d) Indian Standard Institute
To a sample of dal a student added a few drops of iodine solution, what colour change
would be observed?
(a) Colour changes to blue black
(b) Red Colour
(c) Yellow colour of iodine persists
(d) Magenta colour appears
Whcih disease is caused due to adulteration of Kesari Dal in Arhar Dal
(a) Lathyrism
(b) Cancer
(c) Dropsy
(d) Goitre
Metanil yellow is added to food stuff as :–
(a) Vitamin
(b) Adulterant
(c) Flavouring agent
(d) Preservative
In animals, carbohyderates are stored by :–
(a) Cellulose
(b) Glycogen
(c) Starch
(d) Glucose
Which is a reducing agent?
(a) Glucose
(b) Surcose
(c) Fructose
(d) Both (a) and (c)
(534)
X-Science (E.M.)
7.
Name the sugar found in beetroot
(a) Sucrose
8.
(b) Glucose
(c) Maltose
To observe starch granules in potato under a microscope, freshly cut surface of potato
was pressed on a slide. The strain that will show starch granules clearly is....
(a) methylene blue (b) iodine
9.
10.
(d) Fructose
(c) safranin
(d) Acetocarmine
Epidemic dropsy is caused by :–
(a) Vegetable oil in desi ghee
(b) Argemone oil in mustard oil
(c) Coconut oil in musturd oil
(d) none of these
Paul was running with the bottle of iodine tincture. A few drops of iodine fell on his
yellow shirt and few drops fell on white table cloth. The shirt shows blue spot whereas
the table cloth shows the yellow spot. What is the scientific reason for this?
(a) shirt was dyed with metanil yellow
(b) shirt was starched after washing
(c) table cloth was starched but shirt was not
(d) shirt has absorbed the sugar
11.
In fig. The food extract has :–
(a) Sugar
12.
(b) Starch
(c) Protiens (d) Fats
The teacher asked the students to correctly record results of the experiment done to
detect presence of metanil yellow in the adultered arhar dal (tuvar dal) sample that was
provided to them.
(A)
(B)
(C)
(D)
Procedure
5g dal + 5g metanil yellow
5g dal + 5ml water + 2 drops
of HCl
5g dal + 5ml water + pinch of
metanil yellow
5g dal + 5ml water + 2 drops
of HCl
Observation
Inference
dal turns yellow
metanil yellow present
solutions turns pink metanil yellow present
in the sample
water turns yellow metanil yellow present
water turns yellow metanil yellow present
and then pink
The correct recording of the experiment is noted in table
(a) A
(b) B
(c) C
(535)
(d) D
X-Science (E.M.)
Experiment - 14 (IX)
AIM :– To study the characterstics of spirogyra / Agaricus , Moss / Fern, Pinus and an
Angiospermic plant.
1.
2.
3.
Pond silk is
(a) Ulothrix
(b) Spirogyra
(c) Oedogonium
(d) Nostac
Which group is called as amphibians of plant kingdom?
(a) Algae
(b) Bryophyta
(c) Gymnosperms
(d) Angiosperms
In the sporophyte of ferm, identify the part labelled as X
(a) Stem
(b) Seta
(c) Stalk
(d) Petiole
4.
5.
6.
Spirogyra cell starch is stored in
(a) Pyrenoid
(b) Nucleus
(c) Vacoule
(d) Nucleolus
A structure when is present in the slide of spirogyra and onion peel but is not found in
the cheek epethelial cell is :–
(a) cell wall
(b) nucleus
(c) membrane
(d) cytoplasm
Underground stem in pteriodphytes is also called as
(a) Rhizoids
(b) Rhizome
(c) Ramenta
(d) Tuber
(536)
X-Science (E.M.)
7.
8.
9.
Which organism can be found on dead organic material
(a) Moss
(b) Clamydomonas
(c) Agaricus
(d) Cuscutta
In pinus, mature seeds develop in
(a) 1st year cone
(b) 2nd year cone
(c) 3rd year cone
(d) 4th year cone
Diagram of spirogyra were lebelled by two students as given
The correct labelled diagram is :–
(A) A
(b) B
(c) Both are correct
(A)
(B)
(d) None is correct
10.
11.
12.
Flower is a :–
(a) modified branch
(b) modified root
(c) modified leaf
(d) none of these
Mycellium and hyphae are found in
(a) Algae
(b) Lichens
(c) Fungi
(d) All of these
Parts of Agaricus are labelled as A, B, C, D
A
B
(a) hyphae, pileus, stipe, gills
(b) pileus, gills, stipe, hyphae
C
(c) pileus, gills, hyphae, stipe
(d) gills, stipe, pileus, hyphae
D
(537)
X-Science (E.M.)
Experiment - 15 (IX)
AIM :– To study the animals belonging to various groups.
1.
2.
3.
4.
5.
6.
Earthworm belongs to phylum :–
(a) Annelida
(b) Arthropoda
(c) Ostrich thyes
(d) Aves
Body of cockroach is divided into how many parts :–
(a) 1
(b) 2
(c) 3
(d) 4
How many pairs of legs are found in cocoroach :–
(a) one pair
(b) 2 pairs
(c) three pairs
(d) four pairs
Position of a mouth in a bony fish is :–
(a) Terminal
(b) Ventral
(c) Dorsal
(d) Anal
Which of the following has jointed legs?
(a) Earthworm
(b) Bony Fish
(c) Bird
(d) Cockroach
Identify the common feature for which a honey bee and a cockroach are put in one
phylum.
(a) Antenna
(b) three pair of legs
(c) joint legs
(d) wings
(538)
X-Science (E.M.)
7.
Choose the correct options for spiracles
(a) D
8.
10.
11.
12.
13.
(c) C
(d) B
The total number of compound eyes in a cockroach is / are
(a) 0
9.
(b) A
(b) 3
(c) 1
(d) 2
Pneumatic bones are found in
(a) Reptiles
(b) Aves
(c) Chondricthyes
(d) Ostrich thyes
In cockroach, Spiracles helps in :–
(a) Circulation
(b) Excretion
(c) Respiration
(d) Locomotion
The food of earthworm is
(a) humus rich soil
(b) dry leaves
(c) small living insects
(d) algae and fungi
Which segments of the body of earthworm are referred as clitellum
(a) 18 – 20
(b) 10 – 12
(c) 14th and 20th
(c) 14 – 16
Which of the following is a feature of male cockroach only.
(a) Brood pouch
(b) Anal styles
(c) Compound eye
(d) Chitinous plates
(539)
X-Science (E.M.)
14.
Correct order of labelling in the diagram of earthworm is :—
D
B
C
A
(a) Mouth – Segment – Clitellum – Anus
(a) Mouth – Anus – Segment – Clitellum
(a) Mouth – Clitellum – Segment – Anus
(a) Clitellum – Mouth – Segment – Anus
(540)
X-Science (E.M.)
Answers (IX)
5. d
6. a
Experiment - 1
7. d
8. a
9. d
10. c
11. a
12. c
13. a
14. d
1. b
2. c
3. d
4. d
5. a
6. d
7. b
8. a
9. a
10. b
11. b
12. b
13. c
Experiment - 2
1. a
2. c
3. c
4. d
5. d
6. c
7. c
8. c
9. c
10. d
11. d
Experiment - 3
Experiment - 5
1. c
2. c
3. c
4. c
5. b
6. d
7. b
8. a
9. d
10. n
11. c
12. d
Experiment - 6
1. b
2. a
3. a
4. b
5. c
6. d
7. c
8. a
9. c
10. c
11. a
12. d
1. d
2. c
3. c
4. b
5. c
6. c
7. d
8. d
9. c
10. b
1. b
2. a
11. a
12. d
3. b
4. d
13. d
14.c
5. b
6. d
15. d
16. d
7. d
8. b
17. c
18. b
9. d
10. a
19. b
20. b
11. b
21. b
22. a
Experiment - 7
Experiment - 8
Experiment - 4
1. a
2. a
1. c
2. b
3. a
4. b
3. b
4. b
5. c
6. a
(541)
X-Science (E.M.)
7. d
8. a
9. c
10. c
1. d
2. c
11. b
12. b
3. a
4. c
5. b
6. d
Experiment - 9
7. a
8. b
1. c
2. b
9. b
10. b
3. a
4. d
11. b
12. b
5. d
6. c
7. a
8. c
9. d
10. b
1. b
2. b
11. c
12. d
3. b
4. a
5. a
6. b
Experiment - 10
7. c
8. c
1. b
2. d
9. b
10. d
3. b
4. b
11. c
12. b
5. d
6. a
7. b
8. a
9. a
10. c
1. a
2. c
11. d
12. d
3. c
4. a
5. d
6. c
Experiment - 11
7. c
8. d
1. d
2. c
9. b
10. c
3. c
4. b
11. a
12. d
5. c
6. a
13. b
14. c
7. a
8. c
9. b
10. d
Experiment - 13
Experiment - 14
Experiment - 15
Experiment - 12
1. a
2. c
3. b
4. b
5. a
6. b
7. a
8. b
9. c
10. a
(542)
X-Science (E.M.)
MULTIPLE CHOICE QUESTIONS (Based on each experiment)
Experiment - 1
Q. 1
Q. 2
Q. 3
Q. 4
A student was asked to place a drop of solution 's' on a pH paper, deep blue colour
appeared on the strip solution 'S' should be.
(a) Hydrochloric acid
(b) Sodium Hydroxide
(c) Water
(d) Acetic acid (ethanoic acid)
The two colours seen at the periphery of pH chart are:(a) Red and blue
(b) Red and Green
(c) Green and Blue
(d) Orange and Green
Which one of the following solution with some concentration will have lowest value of
pH?
(a) Sodium bicarbonate (NaHCO3)
(b) Hydrochloric acid (HCl)
(c) Sodium hydroxide (NaOH)
(d) Ethanoic acid (CH3COOH)
Which one is the correct figure of method to find the pH of a solution.
I
Q. 5
II
III
(a) IV
(b) III
(c) II
(d) I
IV
What is the correct increasing order of the pH values of the following solution with equal
concentration.
(a) HCl, NaOH, CH3COOH
(b) HCl, CH3COOH, NaOH
(c) NaOH, HCl, CH3COOH
(d) CH3COOH, HCl, NaOH
(543)
X-Science (E.M.)
Q. 6
Which one is the correct statement with referenace to universal indicator?
(a) It is a mixture of HCl and NaOH
(b) It is a mixture of many indicator
(c) It is a solution of Phenolphthalein in alcohol
(d) It is a solution of phenolphthalein in water
Q. 7
Q. 8
Q. 9
The pH of a sample of pure water is 7 at room temperature. What will be its pH when
a pinch of solid sodium carbonate is dissolved in it.
(a) very near to 7
(b) Less than 7
(c) More than 7
(d) exactly 7
For acidic medium the pH value is always :–
(a) Less than 7
(b) equal to 7
(c) equal to 0
(d) greather than 7
pH value of a solution signifies whether the substance is :–
(a) acidic
(b) alkaline
(c) neutral
(d) all of these
Q. 10 A solution has pH = 10.5. It will
(a) turn blue litmus to red
(b) turn red litmus to blue
(c) no effect on litmus
(d) turn blue litmus yellow
Q. 11 Four solutions I, II, III and IV were given to a student to test their acidic or basic nature
by using a pH paper. He observed that the colour of pH paper turned to Red, Blue,
Green and Orange respectively when dipped in four solutions, the correct conclusion
made by the statement would be that :(a) I, II and III are acidic.
(b) I and IV are acidic.
(c) II, III and IV are basic.
(d) II and IV are basic
Q. 12 Observe the following figures and choose the correct option.
(a) pH of I is greater than pH of II and III.
(b) pH of III is greater than pH of I and II.
(544)
X-Science (E.M.)
(c) pH of I, II, III is equal.
(d) pH of II is greater than pH of I & III.
dil HCL
Water
NaOH Solution
Q. 13 A students was given four unknown colourless samples labelled A, B, C and D and
asked to test their pH usig pH paper. He observed that the colour of pH paper turned to
light green, dark red, light orange and dark blue with samples A, B, C and D respectively.
(a) A < B < C < D
(b) A < D < C < B
(c) C < B < A < D
(d) B < C < A < D
(545)
X-Science (E.M.)
Experiment - 2
Q. 1
Q. 2
Q. 3
Q. 4
Q. 5
Which gas is liberated when HCl reacts with Zinc metal.
(a) hydrogen
(b) chlorine
(c) oxygen
(d) nitrogen
Which gas is liberated with HCl reacts with Na2CO3?
(a) hydrogen
(b) carbondioxide
(c) oxygen
(d) carbon monoxide
What is effect of HCl on litmus paper, choose correct option :–
(a) it turns red litmus to blue
(b) it turns red litmus to green
(c) no change
(d) none of these
Which of the chemical reaction represents the reaction between zinc and hydrochloric
acid.
(a) 2Zn + 2 HCl → 2ZnCl + H 2
(b) Zn + 2 HCl → ZnCl2 + H 2
(c) 2Zn + 2 HCl → Zn2Cl2 + H 2
(d) Zn + HCl → ZnCl + H
Zinc metals shows amphoteric nature, it is due to which one of the following facts
(a) Zn reacts with HCl only
(b) Zn reacts with NaOH only
(c) Zn reacts with HCl and NaOH both (d) Zn does not reacts either with HCl or NaOH.
Q. 6
Q. 7
What is form of Zinc metal available for performing experiment in the laboratory.
(a) Zinc fillings
(b) Zinc rod
(c) Zinc granules
(d) Zinc pallets
What is the correct chemical name of Na2ZnO2 –
(a) Sodium zinc oxide
(b) Sodium zinc dioxide
(c) Di Sodium zinc oxide
(d) Sodium zincate
(546)
X-Science (E.M.)
Q. 8
A student added dil. HCl to a test tube containing Zn granules and made following
observations :–
(i) zinc surface become dull and black
(ii) a gas evolved which burn with a pop sound
(iii) the solution remained colourless
Q. 9
(a) I and II
(b) I and III
(c) II and III
(d) I, II and III
Four students I, II, III and IV were asked to examine the changes for blue and red litmus
paper strips with dilute HCl (solution A) and dilute NaOH (solution B). The following
observations were reported by the four students. The sign (–) indicating no colour change.
Litmus
A
B
Litmus
A
B
Blue
___
Red
Blue
Red
___
Red
___
Blue
Red
___
Blue
(I)
(II)
Litmus
A
B
Litmus
Blue
Red
Red
Blue
Blue
Blue
Red
Blue Blue
Red
Red
Red
(III)
A
B
(IV)
The correct observation would be of the student.
(a) I
(c) II
(b) III
(d) IV
(547)
X-Science (E.M.)
Experiment - 3
Focal length (Concave mirror and convex lens)
Q. 1
While performing the experiment for determination of focal length of a convex lens, some
students obtained the image of a distant tree on the screen which one of the following
diagrams represents correctly the image of tree on the screen.
(a) A
Q. 2
Q. 3
(b) B
(c) C
(d) D
In an experiment the image of a distant object formed by a concave mirror is obtained
on a screen. To determine the focal length of the mirror, you need to measure the
distance between the:(a) Mirror and the screen
(b) Mirror and the object
(c) Object and the screen
(d) Mirror and the screen and also between the object
and the screen.
The image formed by concave mirror is real. The position of the screen should be
(a) behind the mirror
(b) on the same side of object between focus and infinity
(c) on the same side of object between focus and pole
(d) none of these
Q. 4
In the experiment to determine focal length of a convex lens, a student obtained a sharp
inverted image of a distant tree on the screen behind the lens. She then removed the
screen and looked through the lens in the direction of the object. She will see:(a) An inverted image of the tree at the focus.
(548)
X-Science (E.M.)
(b) No image as the screen has been removed.
(c) A blurred image on the wall of the laboratory.
(d) An erect image of the tree on the lens.
Q. 5
While performing the experiment for determination of focal length of a convex lens by
using the sun as a distant object a student could not find a screen with stand. Which one
of the following methods he should adopt safely? He should see:(a) The image of sun directly through convex lens.
(b) Focus the image of sun on his hand\
(c) Focus the image of sun on his nylon shirt.
(d) Focus the image of sun on the wall of the room.
Q. 6
In an experiment to determine the focal length of a convex lens, the image of a distant
tree is obtained on the screen. To determine the focal length of the lens, you are required
to measure the distance between the :(a) Lens and the tree only
(b) Lens and the screen only
(c) Screen and the tree only
(d) Screen and the tree and also between the screen and the lens
Q. 7
For performing an experiment, a student was asked to choose one concave mirror and
one convex lens from a lot of mirrors and lenses of different kinds. The correct procedure
adopted by her will be :(a) To choose a mirror and lens which can form an enlarged and inverted image
of an object.
(b) To choose a mirror which can form a diminished and erect image and a lens
which can form an enlarged and erect image of the object.
(c) To choose a mirror and lens which can form an enlarged and erect image
of an object.
(d) To choose a mirror and a lens which can form a diminished and erect image
of an object.
Q. 8
Four students, Ameeta, Zahira, Ravi and David performed the experiment for determination
of focal length of a concave mirror separately. They measured the distance between the
screen and the mirror as shown in the following diagram. Which one of these students
is likely to get the correct value of focal length of the concave mirror?
(549)
X-Science (E.M.)
Davi
(a) Ameeta
Q. 9
(b) Zahira
d
(c) Ravi
(d) David
Your school laboratory has one large window. To find the focal length of a concave
mirror using one of the walls as the screen, the experiment may be perfomed.
(a) Near the wall opposite to the window.
(b) On the same wall as the window
(c) On the wall adjacent to the window
(d) Only on the table as per the laboratory arrangement
Q. 10 A students obtains a blurr image of a object on a screen by using a concave mirror. In
order to obtain a sharp image on the screen, he will have to shift the mirror :–
(a) towards the screen
(b) away from the screen
(c) either towards or away from the screen depending upon the position of the object
(d) to a position very far away from the screen
Q. 11 The focal length of the concave mirror in an experimental setup shown below, is :–
(a) 10.2cm
(b) 11.0cm
(c) 11.4cm
(550)
(d) 12.2cm
X-Science (E.M.)
Q. 12 A students performs an experiment on finding a focal length of a convex lens by keeping
a lighted candle on one end of laboratory table, a screen on its other end and the lens
between them as shown in the figure. The positions of the three are adjusted to get a
sharp image of the candle flame on the screen by making.
(a) the screen in the direction of the lens or the lens in the direction of the screen
(b) the screen in the direction of the lens or the lens away from the screen
(c) the screen away from the lens or the lens in the direction of the screen
(d) neither the screen nor the lens.
Q. 13 Given below are few steps (not in proper sequence) followed in the determination of
focal length of a given convex lens by obtaining a sharp image of a distant object.
(i) Measure the distance between the lens and screen
(ii) Adjust the position of the lens to form a sharp image.
(iii) Select a suitable distant object.
(iv) Hold the lens between the object and the screen with its faces parallel to the screen.
The correct sequence of steps for determination of focal length is
(a) (iii), (i), (iv), (ii)
(b) (iii), (iv), (ii), (i)
(c) (iii), (i), (ii), (iv)
(d) (i), (ii), (iii), (iv)
(551)
X-Science (E.M.)
Experiment - 4
Rectangular Glass Slab
Q. 1
In the glass slab experiment shown below, four students A, B, C and D did the following:A : Kept the eyes far from the glass slab while placing both the pins P3 and P4.
B : Kept the eye close to the glass slab while placing both the pins P3 and P4.
C : Kept the eyes close to the glass slab while placing pins P3 and far from the slab while
placing P4.
D : Kept the eyes far from the glass slab while placing pin P3 and close to the slab while
placing pin P4.
The correct procedure is that of student.
(a) A
Q. 2
(b) B
(c) C
(d) D
A student performed the experiment of glass slab and with different angles of incidence,
measured the angles of refraction and emergence in each case. He then recorded his
observations in the table as given.
S.No. Angle of
Incidence
A
300
Angle of
refraction
Angle of
emergence
250
300
B
400
420
400
C
500
500
500
D
600
600
620
The correct observation is that of :–
(a) A (b) B (c) C (d) D
Q. 3
In an experiment to trace the path of a ray
of light passing through a rectangular
glass slab, the correct measurement of
angle of incidence refraction (r) and
emergence (e) is shown in diagram is:(a) A
(b) B
(c) C
(d) D
(552)
X-Science (E.M.)
Q. 4
An experiment of tracing the path of light lays through a glass slab was set up in the
laboratory and ray diagram was drawn as shown.
The teacher asked the students to identify refracted ray. The correct answer is :(a) PQ
Q. 5
(b) QR
(c) N1N2
(d) RS
Four students showed the following traces of the path of a ray of light passing through
of rectangular glass slab.
The trace most likely to be correct is that of student:(a) A
Q. 6
(b) B
(c) C
(d) D
Out of the four set ups of fixing the pins as shown, while tracing the path of ray of light
through a rectangular glass slab, the most appropriate and preferred position of pins is:(a) A
(b) B
(c) C
A
B
C
D
(553)
(d) D
X-Science (E.M.)
Q. 7
Which of the following figures shows the travelling of light from rarer (R) to denser (D)
medium?
(I)
Q. 8
(II)
(III)
(a) Figure (I) and (IV) only
(b) Figure (II) and (III) only
(c) Figure (III) only
(d) Figure (I) only
Four students reproted the following observation tables for the experiment to trace the
path of a ray of light passing through a glass slab for different angles of incidence. The
observations, likely to be correct are those of student.
∠i
∠r
∠e
∠i
∠r
∠e
300
400
300
300
200
300
400
500
400
400
300
400
500
600
500
500
400
500
(A)
(B)
∠i
∠r
∠e
∠i
∠r
∠e
300
200
400
300
200
200
400
300
500
400
300
300
500
400
600
500
400
400
(C)
(a) A
Q. 9
(IV)
(D)
(b) B
(c) C
(d) D
A ray of light is incident on one of the parallel faces of a rectangular glass slab. It
emerges out of the opposite parallel face making an angle of emergence
(a) equal to angle of incidence
(b) greater than angle of incidence
(c) smaller then angle of incidence
(d) equal to zero
(554)
X-Science (E.M.)
Q. 10 A ray of light incident on one of the parallel faces of rectangular glass slab, emerges out
of the opposite parallel face
(a) inclined to the incident ray
(b) along the same straight line as the incident ray
(c) parallel to the incident ray but laterally displaced
(d) get absorbed into the body of the glass slab and does not emerge out of it.
Q. 11 While performing an experiment of referaction of light through glass slab four students
gave the following conclusion after their observations. Whose conclusion is correct.
(a) Ði = Ðr = Ðe
(b) Ði < Ðr
and
Ðr = Ðe
(c) Ði > Ðr
and
Ðr > Ðe
(d) Ði = Ðe
and
Ðr < Ði
Q. 12 A student traces the path of a ray of light passing through a rectangular glass slab.
For measuring the angle of incidence, he must position the protector in the manner
shown in figure.
(a) A
(b) B
(c) C
(555)
(d) D
X-Science (E.M.)
Experiment - 5 (X)
Ohm's Law
Q. 1
Potential difference between two points A and B on a conductor carrying current is equal
to the :–
(a) work done to move a unit charge from A to B
(b) work done to move a unit from infinity to point A
(c) the rate at which work done is consumed
(d) none of these
Q. 2
Out of four circuits shown for studying the dependence of the current on the potential
difference across a resistor the correct circuit is:(a) A
Q. 3
(b) B
(c) C
(d) D
The plot correctly showing the dependence of the current (I) on the potential difference
(V) across a resistor R is:(a) A
(b) B
(c) C
(d) D
(556)
X-Science (E.M.)
Q. 4
Four students measure the following readings by observing the position pointer in the
ammeter as shown the correct reading is:(a) 2.3A
(b) 2.0A
(c) 5A
(d) 2.05A
Q. 5
Q. 6
Rheostat is used to vary –
(a) current
(b) potential difference
(c) power
(d) resistance
All connections in the experiment to study the dependence of current (I) on potential
difference (V) were made in one of the four circuits the voltmeter was not showing any
reading, but the ammeter was showing deflection the reason of voltmeter not showing
the reading could be.
(i) Connections at the battery were loose.
(ii) Connections at the ammeter were loose.
(iii) Voltmeter was not connected properly.
(iv) Student forgot to insert the key.
Q. 7
In the experiment on the studying the dependence of current (I) on potential difference
(V), four students set up their circuits as shown below:The best set up is that of:+
(a) Student I
–
+
–
(b) Student II
(c) Student III
(i)
–
–
+
+
+
(d) Student IV
–
+
(ii)
+
–
(iii) –
–
+
–
(iv)
–
+
+
(557)
–
+
+
–
X-Science (E.M.)
Q. 8
A student performed an experiment to study the dependence of current (I) on the potential
difference (V) across a resistor and determine its resistance" by using four cells, each
of 1.5V connecting the cells a shown. Identify the correct combination of cells.
(a) A
Q. 9
(b) B
(c) C
(d) D
A
B
C
D
The least count of ammeter shown is :–
(a) 0.01 A
(b) 0.1
(c) 1.0 A
(d) 0.05 A
Q. 10 Voltmeter is attatched in the circuit to verify ohm’s law in order to measure
(a) current in the circuit
(b) potential difference between two points in the circuit
(c) Resistance of the wire (d) all of the above
Q. 11 In a circuit ammeter is always connected in
(a) parallel
(b) series
(c) either series or parallel
(d) none of these
(558)
X-Science (E.M.)
Q. 12 In the experiment on studying the dependence of current (I) on the potential difference
(V), three students plotted the following graphs between (V) and (I) as per their respective
observations.
The observations, likely to be correct, are those of
(a) Student I only
(b) Student II only (c) Student III only (d) Student I, II and III
Q. 13 The figures given below show the readings of milliammeter and a voltmeter connected
in an electrical circuit. Assuming that the instruments do not have any zero error, the
correct readings of the milliameter and voltmeter are:(a) 160 mA and 1.1 V
(b) 130 mA and 1.2 V
(c) 103 mA and 1.1 V
(d) 130 mA and 1.5 V
100
3
2
200
1
4
0
5
300
0
mA
V
(559)
X-Science (E.M.)
Experiment - 6
Two resistors connected in series
Q. 1
Q. 2
In a circuit, if a resistors are connected in series, then the currect is
(a) same in every part of the circuit.
(b) different in every part of the circuit
(c) inversaly proportional to the resistance
(d) none of these
The resistors R1 and R2 are connected in:(a) Parallel in both circuits
(b) series in both.
(c) Parallel in circuit I and in series in circuit II.
(d) Series in circuit I and in parallel in circuit II.
Q. 3
In an experiment to find the equivalent
resistance of two resistors in series
combination a student uses the circuit
shown here. The circuit gives.
(a) Correct reading for voltage V but
incorrect reading for current I.
(b) Correct reading for current I but
incorrect reading for voltage V.
(c) Incorrect reading for both current I
and voltage.
(d) Correct reading for both current (I) and voltage (v)
Q. 4
The total voltage across the series combination is equal to the –
(a) same in every part of the circuit
(b) sum of the voltage drop across each resistor
(c) inversely proportional to the resistor
(d) none of these
(560)
X-Science (E.M.)
Q. 5
In the experiment on finding the equivalent resistance of two resistors connected in
series, the voltmeter is correctly connected only in circuit.
(a) I
(b) II
(c) III
+
–
V
+
R1
–
(i)
R2
R1
R2
A
(ii)
–
+
–
+
V
–
–
R2
R1
V
R1
–
+
R2
–
A
A
+
+
+
Q. 7
–
+
+
Q. 6
V
–
A
+
(iii)
(d) IV
(iv)
–
+
–
Identify the resistor which are in series :–
(a) R1 and R2
(b) R1 and R3
(c) R3 and R4
(d) R2 and R3
In the experiment on finding the equivalent resistance of two resistors, connected in
series, four students connected the voltmeter and the ammeter in the manners shown
below.
The correct connections have been made by student.
(a) I
(b) II
+
(c) III
R1
(i)
R1
R2
–
–
+
+
R1
R2
(d) IV
R2
(ii)
–
+
–
–
–
+
–
+
+
R2
R1
–
–
+
+
(iii)
+
–
+
–
+
(561)
–
(iv)
X-Science (E.M.)
Q. 8
Q. 9
Resistance is more when resistors are connected in
(a) series
(b) parallel
(c) either series or in parallel
(d) none of these
Key is plugged in the circuit only when the reading have to be measured. This is done
to stop.
(a) extra temperature
(b) extra energy loss
(c) burning of circuit
(d) All of above
Q. 10 Four student measure the following reading by observing the position of pointer in
voltmeter. Correct reading is :–
(a) 1.25V
(b) 2.0V
(c) 1.75V
(d) 1.9V
Q. 11 When two resistance R1 and R2 are connected in series, then the resultant resistance
R will be
(a) R = R1 + R2
(b) R = R1 × R2
R1
(c) R = R
2
R2
(d) R = R
1
(562)
X-Science (E.M.)
Experiment - 7
Two resistors connected in Parallel
Q. 1
The voltmeter, ammeter and resistance in the circuit shown have been checked and
found to be correct on plugging the key the voltmeter reads 4.5V but the ammeter reads
1.5A.
W
W
This could most likely be because the wires joined to:-
Q. 2
Q. 3
(a) The resistor R1 is loose.
(b) The resistor R2 is loose.
(c) Both the resistors R1 and R2 are loose.
(c) The ammeter terminals are loose.
Following circuit diagram shows the arrangement for determining the equivalent resistance
of two resistors when connected in parallel. 'X' and 'Y' denote the instruments.
(a) X - ammeter Y - voltmeter.
(b) X - voltmeter Y - ammeter
(c) X - ammeter Y - ammeter
(d) X - voltmeter Y - voltmeter
Total current across the parallel combination is
(a) proportional to the resistance.
(b) Inversely proportional to voltage applied across the combination
(c) Sum of the individual current through each branch.
(d) None of these
(563)
X-Science (E.M.)
Q. 4
A student has four resistors each equal to R. He wants to combine all the resistors in
such a way to get the one fourth value of each resistor. The combination is :–
(a) All in parallel
(b) Two in series and two in parallel
(c) Three in parallel and one in series (d) all in series
Q. 5
Q. 6
Which of following instruments does not have plus (+) or minus (–) sign marked on it,
while representing in a circuit diagram.
(a) Rheostat
(b) Ammeter
(c) Voltmeter
(d) Cell
In the experiment on finding equivalent resistance of two resistors, connected in parallel,
the voltmeter and the ammeter have been correctly connected in circuit.
–
+
+
R1
R1
(i)
R2
–
R2
–
+
–
+
–
–
–
+
R2
–
+
R1
R1
R2
–
(iv)
+
+
+
Q. 7
(ii)
+
+
(iii)
–
–
+
(a) I only
(b) II only
(c) III only
(d) IV only
–
Potential difference across the end of both resistance in parallel combination is equal to
the :–
(a) voltage of battery used
(b) ratio of resistance
(c) ratio of current flow in each
(d) none of these
(564)
X-Science (E.M.)
Q. 8
Two students are using the circuits shown here. They are doing the experiment to
finding the equivalent resistance of a :–
+
–
+
R1
R2
R1
R2
–
–
+
+
–
+
–
+
(a) Series combination and a parallel combination, respectively of the two given resistors.
(b) Parallel combination and a series combination, respectively of the two given resistors.
(c) Series combination of the two given resistors in both the case.
(d) Parallel combination of the two given resistors in both the cases.
Q. 9
Three resistance are connected in a parallel with a battery. The current in each resistor
is 1A. The current drawn from the battery is
(a) 1A
(b) 1.5A
(c) 2.5A
(d) 3A
Q. 10 Equivalent resistance of the resistors in parallel is
1
= R1 + R2 + R3 ....
R
(a) R = R1 + R2 + R3 ....
(b)
1
1
1
1
(c) R = R + R + R ....
1
2
3
1
1
1
(d) R = R + R + R ....
1
2
3
Q. 11 In the experiment on finding the equivalent resistance of two resistors, connected in
parallel, the voltmeter has been correctly connected in :R1
R1
R2
–
(i)
R2
–
(ii)
+
+
+
–
+
–
+
+
–
(565)
–
X-Science (E.M.)
R1
R1
(iii)
–
–
R2
+
+
–
+
–
+
(iv)
R2
(a) I
(b) II
(c) III
(d) IV
Q. 12 In the experiment on finiding the equivalent resistance of two resistors, connected in
parallel, two students connected the ammeter in two different ways as shown in given
circuit I & II. The ammeter has been correctly connected in :-
–
(i)
–
+
–
+
R1
R1
R2
R2
+
–
+
+
–
+
(ii)
–
(a) circuit I only
(b) circuit II only
(c) both the circuit I and II
(D) neither of the two circuits
(566)
X-Science (E.M.)
Experiment - 8
Leafpeel (stomata)
Q. 1
Stomata open when guard cells have
(a) more K+
(b) less K+
(c) more abscisic
(d) all of the above
Q. 2
Instrument used in determination of rate of transpiration is
(a) Tensiometer
(b) Auxanometer
(c) Porometer
(d) Potometer
Q. 3
Ascent of water in plant from roots to the tips of leaves is due to
(a) Osmosis
(b) Transpiration
(c) Photosynthesis
(d) Evaporation
Q. 4
In the following sketch of stomata appratus the parts I, II, III, IV were lablelled differently
by four students.
The correct labelling out of the following is
(a) I Guard cell
II Stoma
III Starch granules
(b) I Cytoplasm
II Nucleus
III Stoma
(c) I Guard cell
II Starch
III Nucleus
(d) I Cytoplasm
II Chloroplast
III Stoma
Q. 5
Nucleus
Chloroplast
Stoma
Nucleus
The correct procudure to prepare a temporary mount of a stained leaf epidermis is
(a) A, D, B, C
(c) D, C, B, A
Q. 6
IV
IV
IV
IV
(b) B, A, C, D
(d) C, D, B, A
Which one of the following is not responsible for opening of stomata.
(a) Turgid guard cells
(b) Low humidity
(c) ABA
(d) Cytokinin
(567)
X-Science (E.M.)
Q. 7
A student draws a following sketch of stomotal appratrus and number the parts to label
them. The chloroplast is denoted by :–
(a) 1
(b) 2
(c) 3
(d) 4
Q. 8
A well stained leaf peel mount when observed unclear the high power of a microscope
shows nuclei in
(a) only epidermal cells
(b) only guard cells
(c) guard cells and epidermal cells
(d) Guard cells, epidermal cells and stoma
Q. 9
In the side of the epidermal peel, the parts which appear pink colour after staining with
safranin are :–
(a) Stomota only
(b) Nuclei only
(c) Cell membrane and cytoplasm
(d) All parts in the leaf
Q. 10 Which one of the following will not facilitate the removal of peel on lower epidermis of
the leaf.
(a) sticking nail polish
(b) use of blotting paper
(c) folding and tearing
(d) use of forceps
Q. 11 In which of the following figures the material and coverslip on it is correctly placed.
(a) A
(c) C
A
B
C
D
(b) B
(d) D
Q. 12 While using microscope at first step we always use
(a) low power lens
(b) high power lens
(c) low power for smaller objects and high power for bigger objects.
(d) low power for bigger objects and high power for smaller objects.
(568)
X-Science (E.M.)
Experiment - 9
Photosynthesis (light necessary for it)
Q. 1
Q. 2
Q. 3
Q. 4
To study the plant cell which stain is used
(a) Methylene Blue
(b) Safranine
(c) Acetocymine
(d) None of the above
In which of the following vacuoles are of big size
(a) Plants cells
(b) Animals cells
(c) Both (a) and (b)
(d) None
Photosynthesis is maximum in
(a) Green light
(b) White light
(c) Red light
(d) Blue light
The experiment, “To show light is necessary for photosynthesis” involves following steps.
Select the incorrect step.
(i) After boiling leaf in alcohol and washing in water, place in Fehlings solution to test
for starch.
(ii) Destarch the plant by keeping it in dark for 2-3 days.
(iii) Cover the leaves with black paper strips and expose sunlight for 3-4 hours.
(iv) Select a leaf, remove paper strips and boil in alcohol.
Q. 5
(a) (ii)
(b) (i)
(c) (iii)
(d) (iv)
In an experiment in photosynthesis, students were instructed to cover a portion of leaf
of a destarched potted plant with opaque paper as shown in the figure ‘A’ covered one
of the leaves with red strip “B” with green, “C” with blue and “D” with black. When the
starch test was done after 4 hours, the result showed no starch in
(569)
X-Science (E.M.)
(a) The portion covered with red, green and blue strips
(b) The portion covered with green strip
(c) The portion covered with black and blue strips
(d) any of the covered portions
Q. 6
The figure depicts one of the steps of the experiment. What does labelling (I) denote?
Alcohol
Leaf
(i)
Tripod Stand
Burner
Q. 7
(a) Starch solution
(b) Alcohol
(c) Water bath
(d) Benzene
Before carrying out the test for the presence of starch in a leaf on exposure to sunlight,
the leaf is put into alcohol contained in a beaker and boiled over a water bath. This step
is carried out to
(a) extract starch
(b) desolve chlorophyll
(c) allow water to move into the leaf
(d) make members of the leaf cells more permeable
Q. 8
Q. 9
Identify the part of leaf, which will not have starch even when exposed to sunlight
(a) A
(b) B
(c) A and C
(d) None of these
A student performed the starch test on a leaf. Some steps involved are shown below.
The correct sequence of steps should be
X-Science (E.M.)
(570)
(i)
(ii)
(iii)
(a) (iv), (iii), (ii), (i)
(b) (i), (ii), (iii), (iv)
(c) (ii), (iii), (iv), (i)
(d) (i), (iii), (iv), (ii)
(iv)
Q. 10 While boiling leaf in alcohol, water bath is used because
(a) alcohol is flammable
(b) water is used as coolant
(c) alcohol required H2O for boiling
(d) all of the above
(571)
X-Science (E.M.)
Experiment - 10
CO2 given out during Respiration
Q. 1
Q. 2
The physical process involving the exchange of gases is called
(a) Inhalation
(b) Transpiration
(c) Respiration
(d) Breathing
A students use boiled seeds to perform the experiment CO2 is released during respiration.
His observation would be :–
(a) Water level in the bent tube rises
(b) Water level in the bent tube decreases
(c) Water level in the bent tube remain same
(d) Rise in water level depends on extend of boiling
Q. 3
Q. 4
To show CO2 is released during respiration in flat bottomed flask we take
(a) Dry seeds
(b) Boiled seeds
(c) Germinating seeds
(d) Wet seeds
After performing the experiment to show that germinating seeds give out carbon dioxide
during respiration students drew the following diagrams.
A
B
C
D
The correct diagram is
Q. 5
(a) A
(b) B
(c) C
(d) D
The function of KOH in the experimental setup to show that CO2 is release during
respiration is
(a) to enhance respiration
(b) to release oxegen for respiration
(572)
X-Science (E.M.)
(c) to absorb carbon dioxide released by germinating seeds
(d) to remove water vapour from the flask
Q. 6
In an experiment to demonstrate the CO2 is given out during respiration, “What would
you observe in the delivery tube dipped in w ater.
(a) Water level rises in the delivery tube
(b) Water turns milky and rises in the delivery tube
(c) Water turns milky but does not rise in the delivery tube.
(d) Water level in the delivery tube remains unchanged
Q. 7
In the list of material requirements for the experiment CO2 is released during respiration.
What is missing?
Materials reqired – conical flask, KOH solution, water in a beaker, U shaped tube bent
twice, one hole rubber cork, vaseline, test tube, thread.
(a) Microscope
(b) Germinating seeds
(c) Lime water
(d) Oxygen
Q. 8
In the above experiment water will rise in the tube because :–
(A) Oxygen of the air in the flask will be taken up by the germinating seeds.
(B) Carbon dioxide given out by the germinating seeds will be absorbed by KOH.
(C) Carbon dioxide given out will go through the glass tube and push up water into
the tube.
(D) Moisture in the germinating seeds will reach the water in the beaker through
the delivery tube.
Q. 9
(a) A
(b) B
(c) C
(d) D
In the experimental setup KOH absorbs CO2 in conical flask and there is rise of water
level in bent tube becuase.
X-Science (E.M.)
(573)
(a) concentration difference
(b) diffusion
(c) creation of partial vacuum
(d) all of these
Q. 10 The material used to make connections of the setup air tight is
(a) vaseline
(b) oil
(c) wax
(d) glue
Q. 11 Instead of plain water, which other chemical be used to show CO2 is released during
respiration.
(a) saline water
(b) lime water
(c) sugar solution
(d) coloured water
Q. 12 Before setting up an experiment to show that seeds release CO2 during respiration, the
seeds should be
(a) dried completely
(b) boiled to make them soft
(c) soaked in vineger
(d) kept moist till they germinate
(574)
X-Science (E.M.)
Experiment - 11
Binary fission (Amoeba)
Budding
Q. 1
Q. 2
(Yeast)
The portion shown as (X) in the given diagram is
(a) single 3 celled bud
(b) chain of buds
(c) parent yeast cell
(d) multi cellular yeast
Shubhankar was given two permanent slides, one of binary fission in amoeba and the
other of budding in yeast. He was asked to determine any one difference in the nucleus
of the two. One such difference is
(a) presence of single nucleus each in amoeba, yeast cell and its attatched bud.
(b) presence of two distinct nuclei in amoeba.
(c) presence of two nuclei in a centrally constructed amoeba, one in yeast parent and
one in its bud.
(d) presence of one nucleus in amoeba and two nuclei in yeast and one nucleus in
its bud.
Q. 3
Correct sequence of showing the process of budding in yeast is
(1)
(2)
(3)
(a) 1, 2, 3, 4
(b) 2, 1, 4, 3
(c) 4, 3, 2, 1
(d) 3, 4, 1, 2
(575)
(4)
X-Science (E.M.)
Q. 4
Choose the one which does not show binary fission.
(a) Amoeba
Q. 5
Q. 6
(c) Euglena
(d) Hydra
Label the diagram in the correct sequence.
(a) Cell membrane, nucleus, vacuole
(b) Nucleus, cell membrane, vacuole
(c) Vacuole, cell membrane, nucleus
(d) Nucleus, vacuole, cell membrane
Budding in yeast in illustrated by the diagram.
(i) A
Q. 7
(b) Paramoesium
(ii) B
(iii) C
(iv) D
Identify the mistake in the following sketch of budding in yeast.
(i) Bud is shown to be smaller than parent cell
(ii) Nuclei are present in both bud and parental cell
(iii) Both parent and bud are shown as single cells.
bud
(iv) Bud is wrongly labelled.
Q. 8
Which one of the following diagram most appropriately illustrates binary fission
in amoeba?
(i) I
(ii) II
(iii) III
(576)
(iv) IV
X-Science (E.M.)
Q. 9
Having seen the permanent slide of reproduction in amoeba and yeast under microscope.
Rohit concluded that :(i) amoeba reproduces by binary fission and yeast by budding
(ii) both reproduce by binary fission
(iii) both reproduce by budding.
(iv) amoeba reproduces by budding and yeast by binary fission.
Q. 10 The shape of yeast cells as observed in permanent slide under microscope is:(i) Rectangular
(ii) Irregular
(iii) Spherical / oval
(iv) Elongated
(577)
X-Science (E.M.)
Experiment - 12
Water soaked by Raisins
Q. 1
Q. 2
Q. 3
Resins are soaked in water for determining the percentage of water absorbed by raisins.
The formula, used by a student by determining the percentage of water absorbed, is :–
(a)
Initial weight - Final weight
× 100
Initial weight
(b)
Final weight - Initial weight
× 100
Initial weight
(c)
Final weight - Initial weight
× 100
Final weight
(d)
Initial weight - Final weight
× 100
Final weight
Ragini soaked 25gm of raisins in 125ml of distilled water in beakers A and B each. She
maintained beaker A at 25°C and beaker B at 50°C. After two hours the percentage of
water absorbed will be :–
(a) same in A and B
(b) more in A then in B
(c) more in B then in A
(d) exactly twice as much in B as in A
What is the inference drawn from the experiment to determine the percentage of water
absorbed by raisins.
(a) distilled water enter raisins because of endosmosis
(b) distilled water enter in raisins due to exosmosis
(c) water moves out of raisins due to endosmosis
(d) water moves out of raisins due to exosmosis
Q. 4
The percentage of water absorbed by raisins is
(a) equal to weight to dry raisins
(b) directly proportional to weight of dry raisins.
(c) inversely proportional to weight of dry raisins
(d) none of the above.
Q. 5
The excess water from soaked raisins is removed by
(a) cotton
(b) rubbing the raisins by palm
(c) filter paper
(d) blowing through mouth
(578)
X-Science (E.M.)
Q. 6
The incorrect method soaking raisins in water is :–
1
Q. 7
Q. 8
Q. 9
2
3
(a) 3
(b) 4
(c) 1
(d) 2
4
Parveen performed the experiment to determine percentage of water absorbed by raisins.
The initial weight of raisins is 15gms and final weight is 24gms. The percentage of water
absorbed will be :–
(a) 62.5%
(b) 160%
(c) 60%
(d) 20%
The colour of raisins after soaking them in water becomes :–
(a) darker
(b) colourless
(c) does not change
(d) some becomes light
Equal amount of raisins were put in water as shown in the diagram given below for half
an hour. Identify the case in which maximum absorption of water will be seen.
Fresh water
1
dilute sugar
solution
2
concentrated
sugar solution
3
(a) 1
(b) 2
(c) 3
(d) same on all three cases
(579)
X-Science (E.M.)
Experiment - 13
Types of Reaction
Q. 1
Q. 2
Q. 3
Action of water on quick lime is a
(a) Decomposition reaction
(b) Combination reaction
(c) Displacement reaction
(d) Double displacement reaction
Chemical formula of quick lime is
(a) CaCl2
(b) CaCO3
(c) CaO
(d) Ca(OH)2
This reaction is an example of :–
CaO + H 2O → Ca(OH ) 2
Q. 4
Q. 5
(a) Endothermic
(b) Exothermic
(c) Substitution reaction
(d) none of these
On passing CO2 gas through the product formed by the reaction between CaO and H2O,
solution becomes
(a) Red
(b) Pink
(c) Black
(d) White
Which of the following information about the reaction of CaO and water is not true :–
(a) CaO reacts with water to form slaked lime
(b) CaO reacts with water vigorously
(c) During the reaction the test tube becomes cold
(d) during the reaction the test tube becomes hot
Q. 6
The solution obtained by mixing CaO with water will be a
(a) Acidic solution
(b) Neutral solution
(c) Basic soution
(d) Emphoteric solution
(580)
X-Science (E.M.)
Q. 7
Q. 8
Q. 9
Heating of ferrous sulphate is a reaction called
(a) Displacement reaction
(b) Combination reaction
(c) Decomposition reaction
(d) Double displacement reaction
Colour of ferrous sulphate is
(a) Blue
(b) Pale green
(c) Brown
(d) Grey
When ferrous sulphate is heated its colour changes
(a) pale green to light red
(b) blue to white
(c) brown to black
(d) blue to yellow
Q. 10 The products obtained by the heating of ferrous sulphate are
(a) SO2, FeO
(b) SO3, SO2, Fe2O3
(c) SO3, SO2, FeO
(d) SO3, Fe2O3
Q. 11 When ferrous sulphate (solid) is heated in a glass tube, a solid remained in the glass
tube is
(a) ferrous sulphide
(b) ferric oxide
(c) ferrous oxide
(d) ferrous sulphite
Q. 12 When an iron nail is placed in a copper sulphate solution, its colour changes from
(a) blue to pale green
(b) brown to black
(c) blue to colourless
(d) pale green to milky white
Q. 13 An iron nail is placed in a copper sulphate solution. After ten minutes nail is taken out.
The nail is found coated with :–
(a) black deposit
(b) brown deposit
(c) white deposit
(d) yellow deposit
Q. 14 Displacement of copper from its solution by iron nail shows :–
(a) copper is more reactive than iron
(581)
X-Science (E.M.)
(b) iron is more reactive than copper
(c) both are equally reactive
(d) none of the above
Q. 15 Precipitate formed by the reaction of Barium Chloride and sodium sulphate is :–
(a) sodium chloride
(b) barrium sulphate
(c) barrium sulphite
(d) sodium sulphite
Q. 16 The colour of precipitate formed by the action of barium chloride and sodium
sulphate is
(a) white
(b) pale green
(c) blue
(d) yellow
Q. 17 Which of the following reaction represents the reaction between barrium chloride and
sodium sulphate correctly?
(a) NaSO4 + BaCl2 → BaSO4 + NaCl
(b) Na2 SO4 + BaCl → BaSO4 + NaCl
(c) Na2 SO4 + BaCl2 → BaSO4 + 2 NaCl
(d) NaSO4 + BaCl → BaSO4 + NaCl
(582)
X-Science (E.M.)
Experiment - 14
Reactivity Series of Metals
Q. 1
Q. 2
Q. 3
Which one of the following will form coloured solution in water?
(a) CuSO4
(b) Na2SO4
(c) ZnSO4
(d) Al2(SO4)3
Some crystals of copper sulphate were dissolved in water. The colour of the solution
obtained would be
(a) green
(b) red
(c) blue
(d) brown
Four strips labelled A, B, C and D along with their corresponding colours as shown
below, which of these could be made up of aluminium?
(a) A
Q. 4
A
B
C
Reddish
Brown
Dark Grey
Blackish
grey
(b) B
(c) C
D
Silvery
white
(d)
Four students of a practical group a, b, c, d were assigned the experiment of reaction
of iron nails with copper sulphate separately, which one of the student of group recorded
all the correct observations.
Student
Initial colour of soln.
Final colour of soln.
a
Blue
Colourless
b
Green
Green
c
Blue
Blue
d
Blue
Light green
(583)
X-Science (E.M.)
Q. 5
When an aluminium strip is kept immersed in freshly prepared ferrous sulphite solution
taken in a test tube, the change which is observed is :–
(a) the green solution slowly turns brown
(b) the lower end of the test tube becomes slightly warm
(c) a colourless gas with smell of burning sulphur is observed
(d) light green solution changes to blue
Q. 6
Q. 7
Pieces of zinc metal are added to four different test tubes containing different solutions
in which test tube, no change will be observed.
(a) CuSO4
(b) ZnSO4
(c) H2SO4
(d) NiSO4
Four test tubes a, b, c, d in which solution I, II, III, IV are shown with their colours, what
will be the colour of zinc sulphate.
(a) I
Q. 8
(b) II
(c) III
(d) IV
Which of the following statement is not correct for the following reaction?
Cu + ZnSO4 → CuSO4 + Zn
Q. 9
(a) the reaction does not occur
(b) Cu is less reactive than Zn
(c) the colourless solution is ZnSO4
(d) Zn is less reactive than Cu
Few zinc granules are poured in 4 different solution, decolourisation will be
observed from
Al2(SO4)3
ZnSO4
CuSO4
(584)
FeSO4
X-Science (E.M.)
(a) A & B
(b) C & D
(c) A & C
(d) B & D
Q. 10 The following sets of equipment were arranged and observations made after one hour.
A coating on iron filling was observed in
Al2 ( SO4 )3
ZnSO4
Solution
Solution
CuSO4
Solution
Iron Fillings
I
II
III
(a) I and II
(b) II only
(c) III only
(d) II and III
Q. 11 Tell the correct arrangement of metals in an increasing order of their reactivity towards
water : Zn, Fe, Mg, Na
(a) Fe < Zn < Mg < Na
(b) Fe < Mg < Zn < Na
(c) Mg > Na > Zn > Fe
(d) None of these
Q. 12 Four test tube were taken and marked A, B, C and D respectively. 2ml of solution of
Al2 ( SO4 )3
placed in
placed in
observed
in water was filled in each of the four test tubes. Clean piece of zinc was
test tube A, clean iron nail was put in test tube B, clean copper wire was
test tube C and a clean aluminium wire was placed in test tube D. It was
that no change occur in any of the test tube. The correct inference drawn is
(a) zinc is more active than aluminium
(b) zinc is more active than copper
(c) copper is more active than aluminium
(d) zinc, iron and copper are less active than aluminium
(585)
X-Science (E.M.)
Experiment - 15
Properties of Acetic Acid
Aim : To study the following properties of acetic acid (ethanoic acid, CH3COOH)
(i) odour
(ii) solubility in water
(iii) effect on litmus paper
(iv) reaction with sodium bicarbonate
Q. 1
Which one of the following would be observed when 10ml of acetic acid is added to10ml
of water?
I
(a) II
Q. 2
Q. 3
Q. 4
II
(b) III
III
(c) I
IV
(d) IV
Which one of the formula of ethanoic acid (acetic acid)
(a) NaHCO3
(b) Na2CO3
(c) CH3COOH
(d) CH3CH2OH
Which one of the following has vinegar like odour?
(a) Sodium bicarbonate
(b) Ethanol
(c) Acetic acid
(d) sodium carbonate
On adding blue litmus solution to acetic acid the colour changes to
(a) Red
(b) Blue
(c) Orange
(d) No change in colour
(586)
X-Science (E.M.)
Q. 5
Q. 6
Q. 7
What is the nature of acetic acid?
(a) Basic
(b) Neutral
(c) Acidic
(d) Amphoteric
Which is the correct statement for the solution when 2ml of acetic acid is mixed with
water?
(a) Transparent
(b) Precipitate
(c) Turbid
(d) Separate layer of acid
For testing the effect of vapours of acetic acid on litmus paper, the litmus paper :–
(a) should be moist
(b) should be dry
(c) may be moist or dry it does not matter
(d) does not give any test
Q. 8
2ml of acetic acid solution is taken in a test tube. On adding a pinch of ‘X’ effervescence
of a gas ‘y’ is produced, which turns lime water milky. Name ‘X’ and ‘y’.
(a) sugar and CO2 gas respectively
(b) common salt and H2 gas respectively
(c) Sodium bicarbonate and CO2 has respectively
(d) Hydrochloric acid more hydrogen gas
Q. 9
Yamini studies the properties of acetic acid in laboratory and recorded the observation
as given in table. Which one is correct record of the following :–
Option
Odour
Solubility in water
Vinegar
Lemon
Partialy soluble
Soluble
a
a
r
a
r
b
a
r
r
a
c
r
a
r
a
d
r
a
a
r
(587)
X-Science (E.M.)
Q. 10 Vasu studies the chemical properties of acetic acid in laboratory. He recorded the
observations in the table given below. The correct option of result would be in :–
Option
effect on litmus
Reaction with NaHCO3
Vinegar
Lemon
Partialy soluble
Soluble
a
a
r
a
r
b
a
r
r
a
c
r
a
r
a
d
r
a
a
r
Q. 11 A student added acetic acid to test tube I, II, III and IV and then introduced a burning
candle near the mouth of each test tube. In which case of candle would not be
extinguished?
(a) I and II
(b) I and III
(c) II and III
(d) II and IV
(588)
X-Science (E.M.)
Answers (X)
11. d
12. b
Experiment No. 1
Experiment No. 5
1. b
2. a
3. b
4. a
1. a
2. b
5. b
6. b
3. a
4. a
7. c
8. a
5. d
6. c
9. d
10. b
7. b
8. a
11. b
12.
9. b
10. b
11. b
12.
b
13. d
13.
b
a
Experiment No. 2
Experiment No. 6
1. a
2. b
3. c
4. b
1. a
2. c
5. c
6. c
3. a
4. b
7. d
8. d
5. c
6. a
7. c
8. a
9. d
10. c
9. b
Experiment No. 3
11. a
1. a
2. a
3. b
4. a
5. d
6. b
1. b
2. b
7. c
8. c
3. c
4. a
9. b
10. a
5. a
6. b
11. b
12. a
7. a
8. b
9. d
10. c
11. a
12. c
13. b
Experiment No. 7
Experiment No. 4
Experiment No. 8
1. a
2. a
3. a
4. b
1. a
2. d
5. b
6. b
3. b
4. b
7. c
8. b
5. a
6. c
9. a
10. c
7. d
8. c
(589)
X-Science (E.M.)
9. d
10. b
11. d
12. a
Experiment No. 9
Experiment No. 13
1. b
2. c
3. b
4. d
5. c
6. c
1. b
2. a
7. c
8. b
3. b
4. a
9. a
10. b
5. d
6. c
11. b
12. a
7. b
8. b
13. b
14. b
9. d
10. a
15. b
16. a
17. c
Experiment No. 10
Experiment No. 14
1. d
2. c
3. c
4. d
1. a
2. c
5. c
6. a
3. d
4. d
7. b
8. b
5. b
6. b
9. c
10. a
7. d
8. d
11. b
12. d
9. b
10. b
11. a
12. d
Experiment No. 11
Experiment No. 15
1. b
2. c
3. b
4. d
1. c
2. c
5. b
6. b
3. c
4. a
7. d
8. b
5. c
6. a
9. a
10. c
7. a
8. c
9. b
10. c
Experiment No. 12
1. b
2. c
3. a
4. b
5. c
6. b
7. c
8. c
11. b
9. a
(590)
X-Science (E.M.)