Download X Science Practice Paper - Brilliant Public School Sitamarhi

Brilliant Public School ,
Sitamarhi
X Science
Practice Paper
Session : 2012-13
Rajopatti,Dumra Road,Sitamarhi(Bihar),Pin-843301
Ph.06226-252314,Mobile:9431636758
Science for Class 10
1. Chemical Reactions and Equations
Q 1 Identify the component oxidised in the following reaction :
H2S + Cl2
S + 2HCl
Mark (1)
Q 2 Define oxidising agent.
Mark (1)
Q 3 Which of the following is a combination and which is a displacement reaction?
(a)
Cl2 + 2KI →
(b)
2K + Cl2
2KCl + I2
→ 2KCl
Mark (1)
Q 4 What is catalytic decomposition?
Mark (1)
Q 5 What are displacement reactions?
Mark (1)
Q 6 What is meant by oxidation?
Mark (1)
Q 7 What is a chemical reaction ?
Mark (1)
Q 8 Define rancidity.
Mark (1)
Q 9 What type of reaction is represented by the digestion of food in our body?
Mark (1)
Q 10 Why does the colour of copper sulphate solution change when an iron nail is dipped in it?
Mark (1)
Q 11 What are double displacement reactions? Give an example.
Mark (1)
Q 12 What are combination reactions?
Mark (1)
X Science C.B.S.E. Practice Paper
Page 1
Q 13 Define the term reduction.
Mark (1)
Q 14 Define the term corrosion.
Mark (1)
Q 15 Why do we apply paint on iron articles?
Mark (1)
Q 16 Write the term used for the symbolic representation of a reaction.
Mark (1)
Q 17 In the following reaction between lead sulphide and hydrogen peroxide:
PbS(s) + 4H2O2(aq) → PbSO4(s) +
4H2
(a) Which substance is reduced?
(b)
Which substance is oxidised?
Mark (1)
Q 18 Identify the substance which is oxidised and which is reduced in the following reaction.
ZnO +C
Zn +CO
Mark (1)
Q 19 Translate the following statements into chemical equations and then balance them.
a)Sodium chloride with sulphuric acid giving sodium sulphate and hydrochloric acid
b)Zinc reacting with silver chloride to give zinc chloride and silver
Marks (2)
Q 20 Packets of potato chips are filled with a gas. Name this gas and explain its use.
Marks (2)
Q 21 What happens when an iron nail is dipped in copper sulphate solution?
Marks (2)
Q 22 Write two uses of decomposition reactions.
Marks (2)
Q 23 Why should magnesium ribbon be cleaned before burning in air?
Marks (2)
Q 24 A solution of a substance „X‟ is used for white washing.
(a) Name the substance „X‟ and write its formula.
(b) Write the reaction of the substance „X‟ named in (a) above with water.
Marks (2)
X Science C.B.S.E. Practice Paper
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Q 25 Write a balanced chemical reaction for each of the following reactions:
(a) Carbon dioxide is passed through lime water which results in the formation of precipitate of calcium carbonate and water.
(b) Precipitate of silver metal is formed when a strip of copper metal is dipped in the solution of silver nitrate solution.
Marks (2)
Q 26 (a)Respiration is considered an exothermic reaction. Why?
(b) Write an example of exothermic reaction.
Marks (2)
Q 27 Explain the term combination reaction with the help of an example.
Marks (2)
Q 28 Write the name of the chemical and its reaction which is used in black and white photography.
Marks (2)
Q 29 Give two examples of redox reactions.
Marks (2)
Q 30 Na2SO4 (aq) +BaCl2(aq)
2 NaCl (s) + BaSO4 (aq)
Is this reaction an example of precipitation reaction? Also give reason for your answer.
Marks (2)
Q 31 Write any four observations that help us to determine whether a chemical reaction is taking place.
Marks (2)
Q 32 Differentiate between combination reaction and decomposition reaction. Give one example of each of these reactions.
Marks (2)
Q 33 ASO4 + B
BSO4 + A
(i) Name this reaction.
(ii) Name the more reactive element.
Marks (2)
Q 34 Write one difference between –
(a) Oxidation and reduction
(b) Exothermic and endothermic reactions
Marks (2)
Q 35 In the following reaction, identify the species that undergoes –
(i) Oxidation
(ii) Reduction
Give reasons also.
Fe(s) + Ni2+ (aq)
Fe2+ (aq) + Ni(s)
Marks (2)
X Science C.B.S.E. Practice Paper
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Q 36 When sodium sulphate solution is treated with barium chloride solution, a white precipitate is formed. Name the reaction and
also write the balanced chemical reaction.
Marks (2)
Q 37 What do you understand by corrosion?
Marks (3)
Q 38 Write the type of chemical reaction represented by the following equations
(i) 2Al(s) +6HCl(aq)
2AlCl3(aq) + 3H2(g)
(ii)2KBr(aq) +Cl2(g)
2KCl(g) + Br2(g)
(iii) 2Zn(s) +O2(g)
2ZnO(S)
Marks (3)
Q 39 What is a precipitation reaction? Give example.
Marks (3)
Q 40 What is the difference between combination and decomposition reaction? Give one example of each type.
Marks (3)
Q 41 (i)What is repiration?
(ii)Is resiration exothermic reaction or endothermic? Explain with reason.
Marks (3)
Q 42 Write the balanced equation for the following chemical reactions(a) Sodium + Water
Sodium hydroxide + Hydrogen
(b) Barium Chloride + Aluminium Sulphate
(c) Hydrogen sulphide + Oxygen
Barium Sulphate + Aluminium Chloride
Water + Sulphur dioxide
Marks (3)
Q 43 What are exothermic and endothermic reactions? Give examples. Marks (3)
Q 44 How a double displacement reaction is different from simple displacement reaction? Explain with the help of an example.
Marks (3)
Q 45 Balance the following chemical equations.
(a) Na + O2
(b) NaCl + H2O
(c) (NH4)2CO3
Na2O
NaOH + Cl2 + H 2
2NH3+ H2O+ CO2
X Science C.B.S.E. Practice Paper
Marks (3)
Page 4
Q 46 Identify the substances that are oxidised and the substances that are reduced in the following reactions.
(a) Fe + CuSO4
FeSO4 + Cu
(b) Fe2O3 +2Al
Al2O3 +2Fe
(c) MnO2 + 4HCl
MnCl2 + 2H2O +Cl2
Marks (3)
Q 47 Explain the terms oxidizing and reducing agents with an example of each.
Marks (5)
Q 48 What is the difference between displacement and double displacement reactions? Write example of each reaction.
Marks (5)
Q 49 What do you understand by a balanced chemical equation? Why should the chemical equation be balanced?
Marks (5)
Q 50 Write balanced chemical reactions which represent the following:
(a) Lead nitrate powder is heated in a test tube.
(b) Ferrous sulphate is heated.
(c) Hydrogen gas combines with nitrogen to form ammonia.
(d) Barium chloride reacts with aluminium sulphate to give aluminium chloride and a precipitate of barium sulphate.
(e) Magnesium metal reacts with water to give magnesium hydroxide and hydrogen.
Marks (5)
Q 51 Balance the following chemical equations.
Marks (5)
Q 52 Represent the following by balanced chemical equations.
(a) Iron nail is kept in a copper sulphate solution.
(b) Silver chloride is kept in sunlight.
(c) Ferrous sulphate is heated at room temperature.
(d) Silver nitrate reacts with hydrochloric acid.
(e) Methane burns in presence of air.
Marks (5)
X Science C.B.S.E. Practice Paper
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Q 53 Write the chemical equation and its type for each of the following:
(a) Silver chloride is exposed to sunlight.
(b) Manganese dioxide reacts with hydrochloric acid.
(c) Zinc rod is dipped in copper sulphate solution.
(d) Solution of sodium sulphate and barium chloride are mixed.
(e) Calcium carbonate is heated.
Marks (5)
Q 54 Write one example of each of the following type of reaction.
(a) Double displacement reaction
(b) Redox reaction
(c) Decomposition reaction
(d) Combination reaction
(e) Displacement reaction
Marks (5)
Q 55 Name the type of following reaction.
(a) Na2SO4 + BaCl2
BaSO4 + 2NaCl
(b) Pb + CuCl2
PbCl2 + Cu
(c) MnO2 + 4HCl
MnCl2 + 2H2O + Cl2
(d) CaO + H2O
Ca(OH)2
(e) 2Pb(NO3)2
2PbO + 4NO2 + O2
Marks (5)
Q 56 When a compound of lead is heated, brown coloured fumes evolve from it.
(i) Name the compound.
(ii) Write the balanced chemical equation.
(iii) Write the chemical name of brown coloured fumes.
(iv) Name the type of reaction.
(v) Is this reaction an exothermic or endothermic?
Marks (5)
X Science C.B.S.E. Practice Paper
Page 6
Most Important Questions
Q 1 Make two separate lists from the given data:-List A comprising of physical changes and List B comprising of chemical changes.
Conversion of water in ice, burning of paper, breaking of glass bottle, rusting of iron, digestion of food ,falling of leaves from tree,
melting of wax candle, Souring of milk
Q 2 Pick and write permanent change/s from following list
Powdering of sugar, sublimation of camphor, digestion of food, mixing of sand and salt, ripening of fruits
Q 3 Is cutting vegetables into small pieces before cooking is physical or chemical change? Give reason for your answer also.
Q 4 Why dissolution of sugar in water is physical change?
Q 5 My friend says souring of milk is a chemical change. Do you agree? Give reasons to support your answer.
Q 6 In the following reaction identify reactant/s and products
X+Y
Z
Q 7 Ammonia is prepared in laboratory according to the following reaction-
Write all the information you; get from this reaction.
Q 8 Write balanced chemical equations for the following chemical reactions
(i) Potassium + Water
Potassium hydroxide + Hydrogen
(ii) Magnesium oxide + Carbon
Magnesium + Carbon dioxide
Q 9 Balance the following reactions
Q 10 Formation of hydrogen chloride is represented as follows
Hydrogen + Chlorine
Hydrogen chloride
Can we call this a chemical equation? Justify your answer.
Q 11 Name the law which is applicable while balancing chemical equations.
Q 12 Represent the burning of magnesium by balance chemical reaction
Q 13 When sulphuric acid is added to zinc granules ,hydrogen gas is evolved along with formation of zinc sulphate. Write balance
chemical equation for the change.
Q 14 Translate the following statements into balance chemical equationsHydrogen sulphide is burned in atmosphere of oxygen to form water and sulphur dioxide
Q 15 Write a balance chemical reaction for formation of water
X Science C.B.S.E. Practice Paper
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Q 16 From the following list select combination reactions, displacement reactions, decomposition and double displacement reaction.
(1)
CaCO3
CaO + CO2
(2)
NH3 + HCl
(3)
Zn + H2SO4
(4)
2H2 + O2
(5)
AgNO3 + NaCl
(6)
2HgO
NH4Cl
ZnSO4 + H2
2H2O
AgCl + NaNO3
2Hg + O2
Q 17 Give an example each of the following types of displacement reactions:
(a) metal displaces metal
(b) non-metal displaces non-metal
Q 18 Identify the substances reduced and the substances oxidized in the following reactions:
(i)
ZnO + C
Zn + CO
(ii)
CuO + H2
Cu + H2O
(iii)
4Na + O2
2Na2O
Q 19 A shiny-brown substance X on heating in air turns black and a new compound Y is formed. Name the substance X and black
compound Y.
Q 20 Is rusting a physical or chemical change?
Q 21 Which process is responsible for the rancidity of fatty foods?
Q 22 When iron nail is dipped in a solution of copper sulphate, a redox reaction takes place:
Fe + CuSO4
FeSO4 + Cu
(i) Name the substance which is reduced and which is oxidised?
(ii) Name the oxidising agent.
Q 23 When magnesium burns in chlorine, it forms Magnesium chloride. On the basis of electron transfer process, state the following
(i) Which element is oxidised?
(ii) Which one is reduced?
Q 24 Oily and fatty food items are flushed with nitrogen gas. Why?
Q 25 Which statement is incorrect for the reaction CuO + H 2
(a)
CuO is reduced
(b)
H2 is oxidised
(c)
CuO is reduced and H2 is oxidised
(d)
Both CuO and H2 are oxidised
X Science C.B.S.E. Practice Paper
Cu + H2O
Page 8
2. Acids, Bases and Salts
Q 1 How does an acid taste?
Mark (1)
Q 2 Name the acid found in (a) Soft drinks (b) Vinegar.
Mark (1)
Q 3 Name the sodium compound which is used for softening hard water.
Mark (1)
Q 4 Name three mineral acids.
Mark (1)
Q 5 Write an equation to show the reaction between Plaster of Paris and water.
Mark (1)
Q 6 What is an indicator?
Mark (1)
Q 7 Define pH.
Mark (1)
Q 8 What is an alkali?
Mark (1)
Q 9 What is a base?
Mark (1)
Q 10 What is the chemical name of washing soda?
Mark (1)
Q 11 What is the common name of the compound CaOCl2?
Mark (1)
Q 12 Name the substance which on treatment with chlorine yields bleaching powder.
Mark (1)
Q 13 What is an acid?
Mark (1)
Q 14 What will happen if a solution of sodium hydrogen carbonate is heated?
Mark (1)
Q 15 How does acetic acid (vinegar) help in the preservation of food? Mark (1)
X Science C.B.S.E. Practice Paper
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Q 16 What is a salt?
Mark (1)
Q 17 What do you mean by universal indicator?
Mark (1)
Q 18 What is a neutralization reaction ?
Mark (1)
Q 19 Why does distilled water not conduct electricity, whereas rainwater does?
Marks (2)
Q 20 Fresh milk has a pH 6. How do you think the pH will change as it becomes sour?
Marks (2)
Q 21 What are acid & base indicators?
Marks (2)
Q 22 What are alkalis?
Marks (2)
Q 23 Why does an aqueous solution of an acid conduct electricity?
Marks (2)
Q 24 How is concentration of hydroxide ions (OH -) affected when excess of base is dissolved in a solution of sodium hydroxide?
Marks (2)
Q 25 What is neutralization reaction?
Marks (2)
Q 26 Why a substance is acidic or basic in nature?
Marks (2)
Q 27 Why should curd and sour substances not be kept in brass and copper vessels?
Marks (2)
Q 28 (a)Sodium hydroxide is prepared by chlor-alkali process.
2NaCl(s) + 2H2O(l)
Cl2(g) + H2(g)+ 2NaOH(aq)
Why this process is called so?
(b) What happens when Plaster of Paris is wetted with water?
Marks (2)
Q 29 A metal compound „X‟ reacts with dilute hydrochloric acid to produce gas (Y). The gas (Y) evolved extinguishes a burning
candle. Write a balanced chemical equation for the reaction if one of the compounds formed is calcium chloride. Write names of x &
y.
Marks (3)
X Science C.B.S.E. Practice Paper
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Q 30 Which gas is usually liberated when an acid reacts with a metal? Illustrate with an example. How will you test for the presence
of this gas?
Marks (3)
Q 31 You have given three test tubes, one of them contain distilled water and the other two contain an acid solution and a basic
solution respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?
Marks (3)
Q 32 (a) Classify tooth paste as an acid or a base.
(b) Give an example each of a natural indicator and a synthetic indicator.
(c)What change in colour of red litmus paper is observed when it is dipped in a test tube filled with an acid?
Marks (3)
Q 33 (a)There are two test tubes - test tube (A) containing HCl and test tube (B) containing NaOH. What changes in colour will be
observed when red cabbage indicator is added to them?
(b)The molecular formula of glucose is C6H12O6. Can we classify glucose as an acid?
Marks (3)
Q 34 Differentiate between Phenolphthalein and Methyl Orange indicators.
Marks (3)
Q 35 (a) Name two edible acids.
(b) Classify aqueous solution of carbon dioxide as acid or base.
(c)Which acid will produce large number of H + ions and why?
(i) aq. solution of acetic acid
(ii) aq. solution of hydrochloric acid
Marks (3)
Q 36 Represent the following by a balanced chemical reaction:
(a)Iron reacts with sulphuric acid. (b)Sodium carbonate reacts with acetic acid.(c)Hydrochloric acid reacts with sodium hydroxide.
Marks (3)
Q 37 (a) Suppose you have an unknown solution (A). How can you find out whether it is acidic or basic or neutral. Name the scale and
its range which can be used for this. (b) Will the pH of orange juice be more than 7 or less than 7?
Marks (3)
Q 38 (a) How does a change in pH causes tooth decay?(b) What are antacids?
Marks (3)
Q 39 What is bleaching powder? How is it prepared? Write chemical equation involved in the preparation of bleaching powder. Write
two uses of bleaching powder.
Marks (5)
Q 40 A compound which is prepared from gypsum has a property of hardening when mixed with water. Identify the compound. Write
the chemical equation of its preparation. Mention two uses of the compound. Marks (5)
Q 41 What is baking soda? How is it produced? Write two uses of it.
Marks (5)
Q 42 Write a short note on pH scale.Marks (5)
X Science C.B.S.E. Practice Paper
Page 11
Most Important Questions
Q 1 Why is it recommended that the acid should be added to water and not water to the acid while diluting it?
Q 2 What happens when: (Support your answer with balanced chemical equations).
1)
Dilute hydrochloric acid reacts with sodium metal.
2)
Magnesium hydroxide is added to nitric acid.
3)
Sodium carbonate is treated with dilute sulphuric acid.
4)
Zinc metal reacts with caustic soda.
5)
Carbon-di-oxide gas is bubbled through potassium hydroxide.
Q 3 Complete & balance the following chemical equations.
1) Mg + H2SO4
2) K2CO3 + 2HCl
3) NaOH + HNO3
4) CuO + 2HCl
Q 4 Distilled water does not conduct electricity whereas rain water does?
Q 5 Classify the following into strong acids and weak acids:
HCl, H2SO4, HNO3, H2CO3, H2SO3, CH3COOH
Q 6 Dilute acids are good conductor of electricity explain?
Q 7 Classify the following into weak and srong bases:
NH4OH, Ca (OH)2, NaOH, KOH, Mg(OH)2
Q 8 Why does dry HCl gas does not change the colour of a dry blue litmus paper?
Q 9 Write one example for each of the following:
1) A mono acidic base –
2) A mono basic acid –
3) A weak base containing no metal ion –
4) A mono basic organic acid –
5) A mineral acid –
Q 10 Name the following:
1) A solution which turns pink on adding caustic soda –
2) A gas, which gives permanent milkiness to lime water –
3) A solution, which turns blue on adding caustic potash –
X Science C.B.S.E. Practice Paper
Page 12
4) The reaction involved in preparation of salts –
5) An acid with two replaceable hydrogen atoms –
Q 11 What is hydrogen ion concentration of an aqueous solution whose pH is 5.
Q 12 Find the pH of 0.01 M HCl.
Q 13 Two solutions A and B have pH values 2 and 9 respectively. Which one of these two will give a pink colour with
phenolphthalein indicator?
Q 14 Give one example for each of the following:
1)
Soluble salt –
2)
Normal salt –
3)
Hydrated salt –
4)
Insoluble salt –
Q 15 Arrange the following in decreasing order of their pH value – Vinegar, fruit juice & water.
Q 16 A colourless gas Y is produced when egg shell is treated with solution X. The gas Y turns lime water milky. What are X & Y?
Q 17 What happens when saturated solution of sodium chloride is electrolysed?
Q 18 Name the following:
1) A metal compound which has detergent properties –
2) A compound used for softening hard water –
3) Two constituents of baking power –
4) Compound of calcium used for disinfecting water –
5) A compound of calcium which hardens on adding water –
Q 19 Write the name and formula of one salt each which contains:
1)
Two molecules of water of crystallization –
2)
Five molecules of water of crystallization –
3)
Ten molecules of water of crystallization –
Q 20 What happens when:
1) Gypsum is heated to 100oC.
2) Chlorine is passed through slaked lime.
3) Sodium hydrogen carbonate is heated strongly.
4) Brine is electrolysed.
X Science C.B.S.E. Practice Paper
Page 13
3. Metals and Non-Metals
Q 1 Write the electron - dot structure for sodium and magnesium.
Mark (1)
Q 2 What are minerals?
Mark (1)
Q 3 What do you understand by ores?
Mark (1)
Q 4 What is gangue?
Mark (1)
Q 5 What chemical process is used for obtaining a metal from its oxide?
Mark (1)
Q 6 In the electrolytic refining of a metal M, what would you take as the anode and the cathode.
Mark (1)
Q 7 Give two examples of metals which can be easily cut with a knife .
Mark (1)
Q 8 Give an example of a metal which (a)
is the best conductor of heat
(b)
is a poor conductor of heat
Mark (1)
Q 9 Write a metal and a non metal which is liquid at room temperature.
Mark (1)
Q 10 Name a metal that is not corroded in air.
Mark (1)
Q 11 What type of oxides are formed when non-metals combine with oxygen?
Mark (1)
Q 12 What are non-metals?
Mark (1)
Q 13 Define ores.
Mark (1)
Q 14 What are amalgams?
Mark (1)
X Science C.B.S.E. Practice Paper
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Q 15 What are alloys?
Mark (1)
Q 16 What chemical process is used for obtaining a metal from its oxides?
Mark (1)
Q 17 Define a chemical bond.
Mark (1)
Q 18 Name the metal foil which is used in packing of some medicines?
Mark (1)
Q 19 What is flux?
Mark (1)
Q 20 What are the metals?
Mark (1)
Q 21 What happens when metals react with acids?
Mark (1)
Q 22 What are amphoteric oxides?
Mark (1)
Q 23 What is Malleability? Give examples
Mark (1)
Q 24 Name two metals which are found in nature in the free state.
Mark (1)
Q 25 What do you understand by activity or reactivity series of metals?
Mark (1)
Q 26 Why the reaction of metals with water, hydrogen and acid cannot be used to compare the reactivity of metals?
Marks (2)
Q 27 Define activity series of metals.
Marks (2)
Q 28 Which type of metals are found in free state in the earth‟s crust?
Marks (2)
Q 29 What do you understand by metallurgy?
Marks (2)
X Science C.B.S.E. Practice Paper
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Q 30 Name two metals which will displace hydrogen from dilute acid and two metals which will not.
Marks (2)
Q 31 What is an alloy?
Marks (2)
Q 32 What do you understand by Aquaregia?
Marks (2)
Q 33 Explain why is sodium Kept immersed in kerosene oil?
Marks (2)
Q 34 Which gas is evolved when magnesium reacts with very dilute nitric acid? Write the equation involved.
Marks (2)
Q 35 Mention examples of metals which react with cold water more violently and less violently each.
Marks (2)
Q 36 What do you understand by metals?
Marks (2)
Q 37 Give two uses of Aluminium.
Marks (2)
Q 38 Why are stainless steel cooking pans often given a copper outer bottom?
Marks (2)
Q 39 Explain why zinc metal can displace copper from copper sulphate solution but copper cannot displace zinc from zinc sulphate
solution.
Marks (2)
Q 40 What are the products formed, when silicon reacts with hydrochloric acid? Write the necessary equation.
Marks (2)
Q 41 What are electrovalent or ionic compounds?
Marks (2)
Q 42 What is Anodiser? Which metal is used for this process?
Marks (2)
Q 43 Why do electrovalent compounds have high melting and boiling points?
Marks (3)
Q 44 Write two advantages and one limitation of using carbon as reducing agent in the metallurgy.
Marks (3)
X Science C.B.S.E. Practice Paper
Page 16
Q 45 Write equation for the reaction of
(a) Calcium with water
(b) Potassium with water
(c) Zinc with dilute hydrochloric acid
Marks (3)
Q 46 What happens when zinc is added to a solution of iron(II) sulphate? Write the chemical reaction.
Marks (3)
Q 47 What is the chemical name and formula of limestone? What happens when limestone is strongly heated? Write the chemical
equation involved. How can the presence of excess of CO 2 be tested in a class room from the products formed.
Marks (3)
Q 48 Differentiate between metal and non – metals on the basis of their chemical properties .
Marks (3)
Q 49 (a)You must have seen that aluminium foils are used for packing food items and silver foils are used for decorating sweets.
Name the property due to which these metals are available in the form of sheets.
(b)Name the metal that is most ductile.
(c)Suppose you have two elements – iron and sulphur. Out of these two, which one is suitable for making a school bell and why?
Name the property also.
Marks (3)
Q 50 What is the difference between calcination and roasting?
Marks (5)
Q 51 Define corrosion of metals? What is rust? How can be rusting prevented?
Marks (5)
Q 52 Represent the formation of MgO and Na2O by the transfer of electrons. Name the ions present in these compounds.
Marks (5)
Q 53 State the major steps usually involved in the metallurgical processes. Name the chief ore of aluminium. Describe with a labelled
diagram and with the necessary chemical equations, how aluminium is extracted from this ore.
Marks (5)
Q 54 What is Froth floatation process ?
Marks (5)
Q 55 What is rusting of iron? Write any two common methods to prevent rusting.
Marks (5)
Q 56 Define allotropy. Name the two common allotropes of phosphorus. Write four differences in the properties of the two allotropes
of phosphorus. Why do they show different properties?
Marks (5)
X Science C.B.S.E. Practice Paper
Page 17
Q 57 (a)You are given two beakers –
(i) Beaker (A) having copper wire immersed in silver nitrate solution.
(ii) Beaker (B) having silver wire immersed in copper nitrate solution.
In which of these beakers, a change in colour will be observed and why?
(b) How can you say that sodium is a metal?
(c) Among gold, sodium, calcium and iron, which one is a soft metal and why?
(d) Name the two metals which do not corrode.
Marks (5)
Q 58 The compound CaO is given to you.and it is also said that it has high melting and boiling points, brittle, soluble in water and
the conductivity is also good in the molten state.Predict the nature of the bond in the compound and justify.
Marks (5)
Q 59 Name the chief ore of aluminium. How it is extracted from the ore?
Marks (5)
Q 60 (a)What property of gold is useful for making jewellery?
(b)When I say that I have a gold chain of 22 carat, what does this mean to you?
(c)Name a metal which is always present in amalgam.
(d)What is solder? Write its one use.
(e) What is stainless steel? Why is it called so?
Marks (5)
Q 61 (a)Name two metals that occur in free state.
(b)Name one ore of mercury.
(c)In order to obtain metal from metal sulphides and metal carbonates, these are first converted into metal oxides. Why?
(d)Name the process in which the sulphide ore is heated in the presence of air.
(e)Write the chemical reaction that takes place during calcination of zinc carbonate.
Marks (5)
Q 62 Represent the following changes by a balanced chemical equation.
(a)Aluminium is heated in air.
(b)Aluminium oxide reacts with hydrochloric acid.
(c)Magnesium reacts with hydrochloric acid.
(d)Iron spoon is put in copper sulphate solution.
(e)Calcium reacts with water.
Marks (5)
Q 63 (a)Name the most widely used method for refining impure metals.
(b) Metals like copper, zinc, tin, nickel, silver, gold, etc. are refined electrolytically. Name the materials used for making anode and
cathode in this method.
(c)Why do we make alloy?
(d)For electrical circuits, we use copper and not brass (an alloy of copper and zinc). Why?
(e)Name the metals that constitute solder.
Marks (5)
X Science C.B.S.E. Practice Paper
Page 18
Most Important Questions
Q 1 Name the following:
a) A metal which is liquid at room temperature:–
b) A non-metal which is liquid at room temperature:–
c) Most abundant metal in the earth‟s crust:–
d) Most abundant non-metal in the earth‟s crust:–
e) A metal which can be cut with knife:–
f) A metal which is poorest conductor of heat:–
g) A metal which is best conductor of heat & electricity:–
h) A metal foil used for packing medicine tablets:–
i) Most ductile metal:–
j) A hard non-metal:Q 2 Justify the statement – Graphite is used for making electrodes.
Q 3 Metals are said to have lusture but usually they appear dull?
Q 4 A metal „X‟ displaces metal „Y‟ from its salt solution. Which will be nearer to the top of reactivity series?
Q 5 What will you observe when a Zinc rod is dipped in copper sulphate solution.
Q 6 In which of the following displacement reaction will take place?
a) Al2(SO4)3 + Cu
No reaction
b) CuSO4 + Fe
FeSO4 + Cu.
Q 7 Which of the following will form basic oxide with air
S, P, Ca, Si ?
Q 8 Metals after hydrogen in the activity series do not react with water, explain.
Q 9 A metal with shining appearance react with hot water and also with hydrochloric acid evolving hydrogen gas. Suggest giving
reason why this metal can not be copper.
Q 10 Why beaker is made of glass and not of Iron?
Q 11 An element „A‟ has two electrons in its valence shell while element „B‟ has seven electrons in its valence shell.
(i) What will be the formula of compound formed between A and B?
(ii) What will be the nature of chemical bond formed
(iii) Will this conduct electricity?
Q 12 Why ionic compounds are good conductors in molten state but not in solid state?
X Science C.B.S.E. Practice Paper
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Q 13 What is the principle behind Thermite welding?
Q 14 Name the components of following alloys
a) Brass
b) Bronze
c) Solder
d) Amalgam
Q 15 Aluminium is more reactive than iron, yet it is more resistant to corrosion, Why?
Q 16 What is galvanization? Why is it done?
Q 17 Name one metal each which is extracted by :
a) Reducing with carbon
b) Electrolytic reduction
c) Reduction with Aluminium
d) Reduction with heat along
Q 18 X, Y, Z are three element which undergo chemical reaction according to following equations.
X2O3 + 2Y
Y2O3 + 2 X
3ZSO3 + 2Y
Y2 (SO4)3 + 3Z
3ZO +
2X
X2O3 + 3 Z
Now answer the following questions.
a) Which element is most reactive
b) Which element is least reactive
c)
Arrange these element in the order of their increasing reactivity.
Q 19 A copper coin is kept immersed in a solution of AgNO3 for some time. What will happen to the coin and colour of the solution.
Q 20 Metals are generally solid at room temperature. Name the metal which is liquid at room temperature.
Q 21 Curd or Chutney is not stored in a vessel made of brass. Give a suitable reason.
Q 22 An element reacts with oxygen to form an oxide which dissolve in dilute HCl. The oxide also turns a solution of red litmus blue.
Is the element a metal or a non metal?
Q 23 An element X burns in oxygen to form a compound XO. What is the formula of compound if this element is made to combine
with chlorine & sulphur.
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Q 24 An ore gives CO2 on treatment with dilute acid. Identify the ore and name the process that should be used to concentrate this and
convert into oxide.
Q 25 What is the mass of gold in a sample of 100g of 20 carats gold.
Q 26 What is solder?
Q 27 What is difference between electrolytic reduction and electrolytic refining.
Q 28 An are gives SO2 on heating. How would you enrich this are.
Q 29 Which are of Cu, Zn, Al and Fe will satisfy the following. Answer with justifications.
a) M2O3 is not affected by water.
b) M form two chloride MCl2 & MCl3
c) One of its Ore is rich in M2O3
Q 30 A trivalent metal X is isolated by the process of electrolysis. It is most abundant metal in the earth‟s crust. Identify the metal and
state its two uses.
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4. Carbon and its Compounds
Q 1 What is hydrogenation?
Mark (1)
Q 2 Why are carbon and its compounds used as fuels for most application?
Mark (1)
Q 3 What is the optimum temperature for fermentation?
Mark (1)
Q 4 Which of the following hydrocarbon undergo addition reactions : C 2H6, C3H8, C3H6, C2H2, and CH4.
Mark (1)
Q 5 What substances are added to ethanol to make it unfit for drinking purposes?
Mark (1)
Q 6 .Name one alcohol which is poisonous
Mark (1)
Q 7 What change will you observe if you test soap with a litmus paper (red and blue)?
Mark (1)
Q 8 Name the type of compounds which give fruity smell.
Mark (1)
Q 9 What is fermentation?
Mark (1)
Q 10 What are the saturated hydrocarbon?
Mark (1)
Q 11 Name the active bacteria for the fermentation of ethanol to produce vinegar.
Mark (1)
Q 12 What reagent will cause conversion of ethanol into ethanoic acid?
Mark (1)
Q 13 Give two uses of ethanoic acid.
Mark (1)
Q 14 What are enzymes?
Mark (1)
Q 15 What is molasses?
X Science C.B.S.E. Practice Paper
Mark (1)
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Q 16 Name the following compounds.
(a)
(b)
Mark (1)
Q 17 Carbon has ability to form long chains of atoms. What is the name given to this property of carbon?
Mark (1)
Q 18 Which of the following would yield an unsaturated hydrocarbon on cracking : C6H14, C2H6, C2H4?
Marks (2)
Q 19 How are carbon fibers made?
Marks (2)
Q 20 What is meant by a functional group in an organic compound?
Marks (2)
Q 21 How is an ester prepared in the lab? Write its one use in daily life.
Marks (3)
Q 22 Name the products formed when methane burns in :
(a) Sufficient supply of air.
(b) Insufficient supply of air.
Write the chemical equations for above reactions.
Marks (3)
Q 23 What are synthetic detergents? Give one example of synthetic detergent. Write its two advantages over soap. Marks (3)
Q 24 (a) Name the functional group present in ethyl alcohol (ethanol).
(b)Write the name and formula of the functional group present in the compound, CH 3COOH. Marks (3)
Q 25 (a) The molecular formula of a hydrocarbon is C6H12. Write the molecular formulae of the members having 9 and 11 carbon
atoms of this homologous series.
(b) Name the reaction.
(c) Vinegar is used as a food preservative. Name the acid present in it.
X Science C.B.S.E. Practice Paper
Marks (3)
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Q 26 Write the names of the functional groups present in the following compounds:
(i) CH3-CHO
(ii) CH3-CO-CH3
(iii) CH3-OH
Marks (3)
Q 27 Name the functional group present in the following compounds.
Marks (3)
Q 28 An organic compound (A) is widely used as a preservative in pickles and has molecular formula C2H4O2. It reacts with ethanol
to form a sweet smelling compound „B‟.
(i) Identify the compound (A).
(ii) Give the chemical reaction equation with ethanol to form compound (B).
(iii) How can we obtain compound (A) back from compound (B)?
Marks (3)
Q 29 What is fermentation? How is ethanol prepared by fermentation? Give two uses of ethyl alcohol. What are the harmful effects of
drinking alcohol?
Marks (5)
Q 30 Compound 'A' is obtained from wood-tar distillation. It has specific smell and burning taste. It burns with blue flame to give CO 2
and H2O. It is soluble in water. It is used as a fuel and solvent. It reacts with sodium metal and gives out hydrogen gas. It reacts with
acetic acid to form pleasant fruity smelling compound 'B' in presence of concentrated H 2SO4. Identify 'A' and 'B' and give equations
for all the reactions involved.
Marks (5)
Q 31 What is meant by homologous series? State any four characteristics.
Marks (5)
X Science C.B.S.E. Practice Paper
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Q 32 Write IUPAC name of the following compounds:
Marks (5)
Q 33 An organic compound (X) with molecular formula C2H6O is generally used as a solvent in cough syrups. It reacts with ethanoic
acid to form sweet smelling compound (Y) and water.
(a) Identify the compound (X).
(b) Write the next member of homologous series to which compound (X) belongs.
(c) Write the balanced chemical reaction when compound (X) reacts with
(i) acetic acid
(ii) conc. H2SO4 at 443 K
(iii) sodium metal
Marks (5)
Q 34 (i) Draw the electron dot structures of
(a) C2H6 (b) C2H4
(ii) Write IUPAC names of the following compounds:
(a) CH3COOH (b) CH3COCH3
(iii) What happens when acetic acid reacts with NaHCO3? Represent it by chemical equation.
Marks (5)
Q 35 (a)Molecular formula of hydrocarbon (A) and (B) are C3H6 and C4H10 respectively. Which of these compounds will undergo
addition reaction and which will undergo substitution reaction easily?
(b) Draw the structures of
(i) Butanone (ii) Pentanal
(c) What is glacial acetic acid?
Marks (5)
Q 36 (a) Write two characteristics of homologous series.
(b) Following reaction is called substitution reaction. Why?
(c) What is esterification reaction?
X Science C.B.S.E. Practice Paper
Marks (5)
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Q 37 (a)What happens when ethanoic acid reacts with
(i) Sodium hydrogencarbonate.
(ii) Sodium carbonate.
(iii) Sodium hydroxide.
(b) Carbon and many of its compounds are used as fuels. Why?
(c) Define catenation.
Marks (5)
Q 38 An organic compound (X) is an active ingredient of all alcoholic drinks. It reacts with ethanoic acid to form sweet smelling
compound and water.
(a) Identify the compound (X) and write its formula.
(b) Write the name of reaction of compound (X) with acetic acid.
(c) Represent the following by balanced chemical reactions.
(i) Compound (X) reacts with sodium metal.
(ii) Compound (X) reacts with sulphuric acid at 170 oC.
(iii) Compound (X) is heated with alk.KMnO4.
Marks (5)
Q 39 (a) Write the chemical formula of the organic acid present in vinegar.
(b) Name the products formed when
(i) ethanol burns in air.
(ii) sodium ethanoate is heated with soda lime.
(c) Will ethanol burn with sooty or non sooty flame? Give reasons also.
Marks (5)
Q 40 Represent the following by balanced chemical reaction
(a) Combustion of Methane
(b)Reaction of ethanol with hot conc. sulphuric acid.
(c)Reaction of methane with chlorine in presence of sunlight
(d)Reaction of ethanol with Sodium Metal Reaction of ethanoic acid with sodium hydroxide
(e)Reaction of ethanoic acid with sodium hydroxide.
Marks (5)
Q 41 (a) Which of the following hydrocarbons undergo addition reactions – C2H6, C3H8, C3H6, C2H2 and CH4?
(b) Explain esterification reaction with an example.
(c) Write characteristics of homologus series.
Marks (5)
X Science C.B.S.E. Practice Paper
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Most Important Questions
Q 1 What is the electronic configuration of carbon and what type of bonds Are formed by it?
Q 2 Name the allotropes of carbon.
Q 3 Explain why graphite is a good conductor of electricity but diamond is a non-conductor of electricity.
Q 4 Name the black substance of pencil. Will the current flow through the electrical Circuit when we use the sharpened ends of pencil
to complete the circuit?
Q 5 What are the two properties of carbon compounds which lead to the formation of a large number of carbon compounds?
Q 6 What are hydrocarbons?
Q 7 Give the general formula of an alkane, alkene and alkyne?
Q 8 What is the molecular formula of a saturated hydrocarbon whose one Molecule contains 8 hydrogen atoms.
Q 9 The molecular formula of an organic compound is C18H36.Name it‟s Homologous series.
Q 10 Name the following compound CH3CH2Br
Q 11 What is the general name of the organic compounds containing the C=O group?
Q 12 Write the formulae of:
Methanoic acid
Ethanoic acid
Q 13 What is hydrogenation?
Q 14 What happens when methane reacts with chlorine? Name the reaction.
Q 15 Explain why, ethene decolorizes bromine but ethane does not?
Q 16 Write the chemical equation of the reaction which takes place during the burning of ethanol in air?
Q 17 What happens when sodium reacts with ethanol?
Q 18 State any two uses of ethanol?
Q 19 What happens when Ethanoic acid reacts with sodium carbonate? Write Chemical equation of the reaction involved.
Q 20 What type of compound is formed when a carboxylic acid reacts with an alcohol in the presence of conc.H2SO4?
Q 21 What is soap? Name one soap.
Q 22 What changes will you observe if you test soap solution with a litmus paper?
Q 23 Why is soap not suitable for washing clothes when the water is hard?
Q 24 What is a detergent? Name one detergent.
Q 25 State one advantage of soap over detergents.
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5. Periodic Classification of Elements
Q 1 Why are the elements in the same group of the periodic table show close resemblance in chemical behaviour?
Mark (1)
Q 2 How many elements were known when Mendeleev classified the elements?
Mark (1)
Q 3 Why do you think the noble gases are placed in a separate group?
Mark (1)
Q 4 What are the limitations of Dobereiner‟s triad?
Mark (1)
Q 5 What was the criteria used by Mendeleev in creating his periodic table?
Mark (1)
Q 6 State the modern periodic law.
Mark (1)
Q 7 How many groups are in the long form of the periodic table?
Mark (1)
Q 8 What is the fundamental difference in the electronic configuration of the group I and group II elements?
Mark (1)
Q 9 Besides gallium, which other elements have been since discovered to fill the gaps left by Mendeleev in his periodic table? (Any
two)
Mark (1)
Q 10 How many periods are present in Modern periodic table?
Mark (1)
Q 11 What is basis of classification of elements?
Mark (1)
Q 12 Which period is the longest period in the modern periodic table?
Mark (1)
Q 13 In the Modern Periodic Table, which are the metals among the first ten elements?
Mark (1)
Q 14 Define group.
Mark (1)
Q 15 Write the K, L, M, N electronic configuration of Ca. (Atomic No. = 20) Mark (1)
X Science C.B.S.E. Practice Paper
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Q 16 Name two elements you would except to show chemical reactions similar to magnesium. What is the base for your choice?
Mark (1)
Q 17 What does each period in the periodic table indicate?
Mark (1)
Q 18 What was the drawback of the law of octaves?
Mark (1)
Q 19 Which is bigger in size and why F or Cl ?
Marks (2)
Q 20 How does the electronic configuration of an atom relate to its position in the Modern Periodic Table?
Marks (2)
Q 21 Nitrogen (atomic number 7) and phosphorus (atomic number 15) belong to group 15 of the periodic table. Write the electronic
configuration of these two elements. Which of these will be more electronegative. Why?
Marks (2)
Q 22 Element X forms a chloride XCl2, which is a solid with a high melting point. X would most likely be in the same group of the
periodic table as:
(a) Na (b) Mg (c) Al (d) Si
Marks (2)
Q 23 Explain why?
(i) All the elements of a group have similar chemical properties.
(ii) All the elements of a period have different chemical properties.
Marks (2)
Q 24 What happens to
(i) Metallic character of the elements as we move from left to right in a period.
(ii) Atomic size when we move from top to bottom in a group.
Marks (2)
Q 25 An element X belongs to group 2 and another element Y belongs to group 15 of the periodic table:(a) What is the number of valence electrons in X?
(b) What is the valency of X?
(c) What is the number of valence electrons in Y?
(d) What is the valency of Y?
Marks (2)
Q 26 What are the advantages of the periodic table?
X Science C.B.S.E. Practice Paper
Marks (2)
Page 29
Q 27 For each the following triads, name the element with the characteristics specified below:
Elements
Smallest
atomic
radius
Chemically
least reactive
F, Cl, Br
…………..
……………
Li, Na, K
……………
…………….
Marks (2)
Q 28 Consider the following elements:
Na, Ca, Al, K, Mg, Li
(a)Which of these elements belong to the same period of the periodic table?
(b)Which of these elements belong to the same group of the periodic table?
Marks (2)
Q 29 An atom has electronic configuration 2, 8, 7:(a) What is the atomic number of this element?
(b) To which of the following elements would it be chemically similar? N (7), F (9), P (15), Ar (18).
Marks (2)
Q 30 By considering their position in the periodic table, which one of the following elements would you except to have the maximum
metallic character?
C , O, F,B, Be
Marks (2)
Q 31 What change will be observed in atomic size when we move from top to bottom in group 2. Give reasons also.
Marks (2)
Q 32 Atomic number of an element is 19.
(i) Is it a metal or non-metal?
(ii)Will the size of this element be greater than that of sodium?
Marks (2)
Q 33 Write the names of
(a) two elements that have seven electrons in their outermost shells.
(b) two elements that have two electrons in their outermost shells.
(c) two elements which have completely filled outermost shells.
Marks (3)
Q 34 Write the demerits of Newlands‟ law of octaves.
Marks (3)
Q 35 Write the merits of Mendeleev‟s classification of elements.
Marks (3)
X Science C.B.S.E. Practice Paper
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Q 36 Write the limitations of Mendeleev‟s classification of elements.
Marks (3)
Q 37 Write the merits of the modern periodic table.
Marks (3)
Q 38 The positions of three elements A, B, and C in the periodic table are shown here.
Group 16
Group 17
-
-
-
A
-
-
B
C
(a) State whether A is a metal or non-metal
(b) State whether C is more reactive or less reactive than A.
(c) Will C be larger or smaller in size than B?
Marks (3)
Q 39 Element P belongs to group 2 of modern periodic table and element Q belongs to group 17 of modern periodic table. Write the
formula of:
(i) the compound formed by element P and Q.
(ii) the oxide of element P.
(iii) the chloride of element P.
Marks (3)
Q 40 An element „X‟ belongs to second period and second group of the periodic table. Find:
(i) the number of valence electrons.
(ii) the valency of the element.
(iii) whether element X forms acidic or basic oxide.
Marks (3)
Q 41 When a metal M reacts with a non-metal X, it forms a compound of MX type.
(a) Identify the group in which element M and X are placed in modern periodic table.
(b) Write the number of valence electrons present in element M and element X.
(c) Write an example of MX type of compound.
Marks (3)
Q 42 An element (X) belongs to second period and first group of the periodic table. Find:
(i) the number of valence electrons present in its atom.
(ii) the valency of the element.
(iii) whether element (X) forms acidic or basic oxide.
Marks (3)
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Q 43 In the following diagram for the first three periods (showing only group 1,2, 13 to 18)of the periodic table, five elements have
been represented by the letters a, b, c, d and e (which are not their chemical symbols):
(i)Select the letter which represents a halogen.
(ii)Select the letter which represents a noble gas.
(iii)What type of bond is formed between a and b?
(iv)What type of bond is formed between c and d?
(v)Which element will form a divalent anion?
Marks (5)
Q 44 Write the characteristics of the groups.
Marks (5)
Most Important Questions
Q 1 Define Mendeleev‟s Periodic Law and Modern Periodic Law.
Q 2 What is the trend of atomic size (radius) on moving down a group?
Q 3 The atomic number of an elenent is12. Write its electronic configuration and find its group.
Q 4 Give an example of Dobernier triad.
Q 5 Give three examples of Dobereiner's triad.
Q 6 What were the limitations of Newland‟s Law of Octaves?
Q 7 Write the merits of Mendeleev‟s Periodic Table.
Q 8 Explain limitations or demerits of Mendeleev‟s Periodic Table.
Q 9 How many number of groups and periods are there in Modern (long form) Periodic table?
Q 10 Write the number of elements present in K, L and M shell periods of Modern Periodic Table and give reason for it.
Q 11 How could the Modern Periodic Table remove various anomalies of Mendeleev‟s Periodic Table?
Q 12 An atom has electronic configuration 2, 8, 7: (a) What is the atomic number of this element?
(b) To which of the following elements would it be chemically similar? Their atomic numbers are given in brackets:
N (7), F (9),
P (15), and
Ar (18)
X Science C.B.S.E. Practice Paper
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Q 13 The position of three elements A, B and C in the periodic table is shown below:
Group 16
Group 17
---
----
---
A
---
---
B
C
(a) State whether “A” is a metal or non-metal?
(b) State whether „C‟ is more reactive or less reactive than A?
(c) Will „C‟ be larger or smaller in size than B?
(d) Which type of ion, cation or anion will be formed by elements A?
Q 14 Explain the trends in the Modern Periodic Table (i) valency (ii) atomic size (iii)Metallic and non-metallic properties
Q 15 Compare the arrangement of elements in Mendeleev‟s periodic table and modern periodic table.
Q 16 In the following set of elements, one element does not belong to the set. Select this element and explain why it does not belong:
Q 17 The atomic numbers of three elements A, B and C are given below:
Element
Atomic Number
A
3
B
9
C
11
Explain with reasons which of these elements will show similar chemical properties.
Q 18 An element A belong to third period and first group of the periodic table. Find :
(i) The number of valence electrons present in its atom.
(ii) Valency of the element.
(iii) If it is metal or non-metal
(iv) Name of the element
(v) Name of the family to which this element belongs.
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6. Life Processes
Q 1 Why is the pH of stomach acidic?
Mark (1)
Q 2 What do you mean by holozoic nutrition?
Mark (1)
Q 3 Give the full forms of ATP and ADP.
Mark (1)
Q 4 What is bile?
Mark (1)
Q 5 Name the muscle regulating the exit of food from the stomach.
Mark (1)
Q 6 Define emulsification.
Mark (1)
Q 7 Name the various factors which affect the rate of photosynthesis.
Mark (1)
Q 8 Why is the rate of respiration faster in aquatic organisms as compared to terrestrial organisms?
Mark (1)
Q 9 Write the values of normal systolic and diastolic pressures in the human body.
Mark (1)
Q 10 What is the pH of stomach acid?
Mark (1)
Q 11 Who gave the classification of blood groups?
Mark (1)
Q 12 Define peristaltic movement?
Mark (1)
Q 13 Name the main nitrogenous waste of humans.
Mark (1)
Q 14 What is the similarity between chlorophyll and haemoglobin?
Mark (1)
Q 15 Why do aquatic animals respire fast?
X Science C.B.S.E. Practice Paper
Mark (1)
Page 34
Q 16 Saliva plays a very important role in digestion. Explain.
Mark (1)
Q 17 Write the methods used by the plants to get rid of their excretory products.
Marks (2)
Q 18 What are the differences between arteries and veins?
Marks (2)
Q 19 Why do herbivores need a longer intestine as compared to the carnivores?
Marks (2)
Q 20 What is peristaltic movement? How are they helpful in human digestion?
Marks (2)
Q 21 Name and write the function of the enzyme present in human saliva.
Marks (2)
Q 22 Write the basic differences between autotrophic and heterotrophic nutrition.
Marks (2)
Q 23 Give the path of the passage of air in the human body?
Marks (2)
Q 24 What is the direction of flow of water in xylem and food in phloem?
Marks (2)
Q 25 What is the cup shaped structure of nephron called? Which materials are selectively reabsorbed by nephron tubule?
Marks (2)
Q 26 Some people are known as universal donors. Explain why?
Marks (2)
Q 27 Bile juice is released from which organ? Give two functions of bile juice. Marks (2)
Q 28 Fill in the vacant column with reference to the digestive glands of man.
Digestive gland
Digestive juices
Salivary gland
Gastric juice
Liver
Pancreatic juice
Marks (2)
X Science C.B.S.E. Practice Paper
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Q 29 What will happen if CO2 is absent during the process of photosynthesis?
Marks (2)
Q 30 Write the technical term for the following:
i) Small openings located on the surface of leaves guarded by two kidney shaped structures.
ii) The entry of air from outside into alveoli of lungs through respiratory tract.
Marks (2)
Q 31 Fill in the missing words in the given table:
Components of blood
Functions
Transports food, hormones, CO2 and nitrogenous
wastes
Transports oxygen and carbon-dioxide
W.B.Cs
Blood platelets
Marks (2)
Q 32 Sketch a flow diagram for the various pathways for breakdown of glucose.
Marks (3)
Q 33 How is lymph formed? Write its functions.
Marks (3)
Q 34 How does the transportation of food takes place in plants?
Marks (3)
Q 35 How do the alveoli of lungs in human body help in the exchange of gases?
Marks (3)
Q 36 Describe what happens to the eaten food in stomach?
Marks (3)
Q 37 What are the three basic events taking place in the process of photosynthesis?
Marks (3)
Q 38 Why is the process of simple diffusion sufficient for taking in food, exchange of gases and removal of waste in unicellular
organism but not sufficient in multicellular organism?
Marks (3)
Q 39 How does the process of nutrition take place in amoeba? Explain with the help of labeled figures.
Marks (3)
Q 40 Draw the figures of an open and a closed stomata.
Marks (3)
X Science C.B.S.E. Practice Paper
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Q 41
i) Name the labelled part (a) and state its main function.
ii) Which chamber of the human heart receives deoxygenated blood?
Marks (3)
Q 42
a) Label the parts (A) and (B).
b) What is the importance of part (A) in the process of photosynthesis?
Marks (3)
Q 43 a) What are the components of transport system in higher group of plants?
b) Give the technical term for absorption of water with the utilisation of energy.
c) Name the process which regulates the temperature of a plant body.
Marks (3)
Q 44 How are carbohydrates, proteins & fats digested in small intestine?
Marks (5)
Q 45 Describe the structure and functioning of nephron in the human body.
Marks (5)
Q 46 Draw a well labelled sectional view of human heart showing the passage of flow of blood.
Marks (5)
X Science C.B.S.E. Practice Paper
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Q 47 a) Differentiate between the following:
i) Renal artery and renal vein.
ii) Active and passive absorption.
b) Draw the figure of a nephron and label the part related to ultra filtration.
Marks (5)
Q 48 a) What would happen if there is a deficiency of haemoglobin in our body?
b) Show the circulation of blood in the human body with the help of sketch only.
Marks (5)
Q 49 a) State any three ways by which plants get rid of their excretory products.
b) What are the disadvantages of transpiration?
Marks (5)
Q 50 (i) Draw a diagram of the cross section of a leaf and label the following parts: a) chloroplast, b) guard cell, c) lower epidermis, d)
upper epidermis, e) mesophyll cells, f) cuticle.
(ii) From where does the plant get each of these raw materials: a) CO 2 b) water c) minerals d) food
[ 3+2 =5]
Marks (5)
Q 51 (i) What do the following transport–
a) xylem, b) phloem, c) pulmonary vein, d) vena cava
(ii) What are the differences between the transport of materials in xylem and phloem?
(iii) Name the term for the transport of food from leaves to other parts of plants.
[2+2 +1 = 5 ]
Marks (5)
Q 52 (i) Draw a well labelled diagram showing the human respiratory system.
(ii) After a vigorous exercise, you may experience cramps in your leg muscles. Why does this happen?
[ 3+2 = 5 ]
Marks (5)
Q 53 (i) Write one function for each of the following components of transport system in human beings.
(a) Arteries (b) Veins (c) Capillaries
(ii) Why do veins have thin walls compared to arteries?
(iii) A thin walled chamber of the heart receives oxygenated blood from the lungs. Name that chamber.
[ 3+1+1= 5 ]
Marks (5)
X Science C.B.S.E. Practice Paper
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Most Important Questions
Q 1 How are the process of respiration and nutrition related to one other?
Q 2 Why excretion is considered to be an important life process?
Q 3 What two requirements of the body are fulfilled through the process of nutrition?
Q 4 In what form carbohydrates are stored in plants?
Q 5 What substance is reduced to produce carbohydrates during the process of photosynthesis?
Q 6 What happens to the stomata when water enters the guard cells?
Q 7 What is the role of stomata in the process of photosynthesis?
Q 8 How many carbon dioxide molecules are needed to form one molecule of glucose?
Q 9 Give an example of a plant parasite.
Q 10 Name the structures used by (i) Amoeba and (ii) Paramecium for obtaining food.
Q 11 On what component of the food the enzyme salivary amylase acts?
Q 12 What causes the movement of food in the alimentary canal?
Q 13 What is the role of mucus in the stomach?
Q 14 Why do cows have longer intestine than tigers?
Q 15 What role does bile juice play in the digestion of fats?
Q 16 What component of the food gives amino acids after digestion?
Q 17 How is small intestine adapted for absorption of digested food?
Q 18 Name the enzymes present in pancreatic juice.
Q 19 Name some of the nutrients required by plants.
Q 20 Which bacteria helps in the fixation of the element required for the synthesis of proteins?
Q 21 Name the two types of cellular respiration. Which of them gives more energy?
Q 22 What is the first step in cellular respiration? Where does this occur?
Q 23 Why do you feel cramps in muscles after strenuous exercise?
Q 24 What prevents the collapse of air passage in the throat?
Q 25 Why alveoli are considered to be a good surface for exchange of gases?
Q 26 Why do humans need a respiratory pigment for transport of gases within the body?
Q 27 What is the difference between the transport of carbon dioxide and oxygen in the body?
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Q 28 How many chambers of heart are present in:
(i) Humans
(ii) Fish
(iii) Reptiles
Q 29 Name the chamber of the heart which:
(a) Receives deoxygenated blood from body parts.
(b) Receives oxygenated blood from lungs.
(c)Pumps blood into the aorta.
(d) Pumps blood into the pulmonary artery.
Q 30 What is the role of valves between atria and ventricles?
Q 31 Why the blood circulation in humans called double blood circulation?
Q 32 Write the main differences between an artery and a vein?
Q 33 Which component of the blood helps in preventing leakage of blood from the site of injury?
Q 34 What are the differences in the transport of water & minerals and transport of food & other substances in the plant?
Q 35 How does transpiration help in transport of water in plants?
Q 36 What factor helps in movement of water in plants at night?
Q 37 Name the wastes present in urine.
Q 38 Which substances are selectively reabsorbed in kidneys?
Q 39 Which plant wastes are stored in old xylem?
Q 40 Why lymph is called tissue fluid?
Q 41 Why breathing rate is faster in aquatic organisms than in terrestrial organisms?
Q 42 What are the products of fermentation of one glucose molecule?
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7. Control and Coordination
Q 1 Which part of the brain gives rise to spinal cord?
Mark (1)
Q 2 What are the names of future shoot and future root in a germinating seed?
Mark (1)
Q 3 Which group of multicellular animals do not posses neurons?
Mark (1)
Q 4 Name the chemical substances which control and coordinate in plants.
Mark (1)
Q 5 Label the parts mentioned as 'A' and 'B' in the given image:
Mark (1)
Q 6 Name the longest cell in our body.
Mark (1)
Q 7 What is cranium?
Mark (1)
Q 8 Why are endocrine glands also known as ductless glands?
Mark (1)
Q 9 Name the part of brain specialised for hearing, smell and sight.
Mark (1)
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Q 10 What are plant hormones? What is the relationship between their site of production and site of action? Marks (2)
Q 11 What is insulin? Where is it produced?
Marks (2)
Q 12 How are the time and amount of hormone released, controlled? Explain with example.
Q 13 What are the two ways of control and coordination in animals?
Marks (2)
Marks (2)
Q 14 What are two different types of plant movements?
Marks (2)
Q 15 Name the hormones secreted at puberty in males and females?
Marks (2)
Q 16 Does thinking also involve the creation of nerve impulses?
Marks (2)
Q 17 How are the brain and spinal cord protected in human body?
Marks (2)
Q 18 What is the reason behind the evolution of reflex arcs? Write the route followed by nerve impulses in the production of a reflex
action.
Marks (2)
Q 19 Fill the missing words in the given table.
Hormone
Deficiency Disease
Iodine
Goitre
Dwarfism
Insulin
Marks (2)
Q 20 Fill in the missing words in the given flow chart:
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Marks (2)
Q 21 Fill in the missing words in the given figure:
Marks (2)
Q 22 (a) Mira planted a seed in her house but the plant is not growing as expected with respect to its length. Which hormone should be
supplied externally to the plant so as to rectify the above discussed problem?
(b) A plant is showing rapid collapse of shoots, branches and leaves as shown in the below given image:
Identify the hormone responsible?
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Marks (2)
Q 23 How do animal muscles move in order to perform an action or movement?
Marks (3)
Q 24 How are the animal movements different from that of plant movements?
Marks (3)
Q 25 Explain the terms Geotropism, Hydrotropism and Chemotropism with one example.
Marks (3)
Q 26 Why is iodine salt necessary for our body?
Marks (3)
Q 27 Why are some people very short and others very tall?
Marks (3)
Q 28 What are involuntary actions? Name few. Which parts of brain control these actions?
Marks (3)
Q 29 How are the information and decision processed in the forebrain?
Marks (3)
Q 30 Fill in the missing words in the given table:
Marks (3)
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Q 31 Fill in the missing words in the given flow chart:
Marks (3)
Q 32 Fill the missing words in the given table.
Marks (3)
Q 33 What is the general scheme of nerve impulses traveling in our body?
Marks (5)
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Q 34 Draw the well-labelled figures of human brain.
Marks (5)
Q 35 a. Define Tropism. What are the basic types of tropism?
b. Explain how nastic movements differ from tropic movements.
c. Name the kind of movement seen in growing pollen tube in a flower.
Marks (5)
Q 36 (a) State two functions of myelin sheath.
(b) Identify the phenomenon shown in the below given diagrams (A) and (B):
(c) Sona‟s grandfather asked her to prepare a cup of coffee for him. He also told her not to add sugar in it as he was suffering from a
hormonal disease. Identify the disease and the hormone responsible for it.
Marks (5)
Q 37 (a) Give the technical terms for:
(i) Bundle of axons enclosed in a tubular sheath.
(ii) Change of external or internal environment that result in a change in the activities of the organism.
(iii) Change of activity in an organism due to stimulus.
(iv) The ability of nerve cells to respond to stimuli and convert them into nerve impulses.
(b) Identify the parts of a neuron:
1. Where is the information acquired?
2. Through what, information travels as an electrical impulse?
3. Where this impulse must be converted into a chemical signal for onward transmission?
Marks (5)
Q 38 (a) Yesterday Ram and his younger brother were stuck in their society lift. Ram observed that his brother‟s face became pale and
his heart was beating very fast. Identify the hormone responsible for the changes in Ram‟s brother.
(b) What made Ram‟s brother look pale?
(c) Differentiate between Nervous Control and Hormonal Control.
Marks (5)
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Most Important Questions
Q 1 Name the two systems that help in control and coordination in animals?
Q 2 Name the stimulus in the following responses:
(a) Hiding of cockroaches when light is switched on.
(b) Growth of roots towards earth.
Q 3 Give examples of situations when the same response is given against different stimuli.
Q 4 Name the part of the neuron:
(a) which receives stimuli.
(b) which transmits electrical signals.
Q5
1.
2.
3.
Name the division of nervous system which includes:
Spinal cord
Cranial nerves
Brain
Q 6 What is the difference between the functions of central and peripheral nervous system?
Q 7 What is the difference between sensory and motor neurons?
Q8
1.
2.
3.
4.
Name the part of the brain which is:
The largest part of the brain.
Helps in controlling involuntary actions.
Helps in thinking process.
Helps in maintaining body posture.
Q 9 Why the brain and spinal cord need to be protected?
Q 10 How the protection is provided to brain and spinal cord?
Q 11 What type of receptors help in detection of (a) taste and (b) smell.
Q 12 How does transmission of information take place through synapse?
Q 13 How the movement is caused in muscles of the hand when a hot plate is touched?
Q 14 What is the difference between reading and a reflex action?
Q 15 Draw a schematic flowchart to represent a reflex arc.
Q 16 Why chemical coordination is required in animals?
Q 17 Why iodine should be included in the diet?
Q 18 Name the hormone which is called “fight or flight” hormone. Which gland secretes it?
Q 19 Name the male and female hormones responsible for changes during puberty? Also specify the organs that secrete them.
Q 20 Why insulin injections are given to a patient of diabetes?
Q 21 What are the two types of movements in plants?
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Q 22 What type of movements are the following:
(a) Winding of a tendril around a support.
(b) Movement of roots towards gravity.
Q 23 How is the movement caused in Mimosa plant?
Q 24 Name the hormone responsible for :
(a) Wilting of leaves.
(b) Growth of stem.
Q 25 How does auxin help a shoot to bend towards light source?
Q 26 Why growth of roots towards earth is a tropic movement?
Q 27 Give an example of each:
(a) Tropic movement away from the stimulus.
(b) Tropic movement towards the stimulus.
Q 28 Give an example of each:
(a) Hydrotropism
(b) Phototropism
(c) Chemotropism
Q 29 Why roots are called negatively phototropic?
Q 30 Name the plant hormone that inhibits growth.
Q 31 How is the movement of sunflower towards the sun different from movement of roots towards the earth?
Q 32 Name the stimulus in the following situations:
(a) Folding of leaves of mimosa.
(b) Growing of shoot of a potted plant in upward direction.
Q 33 What is the role of plant hormones in plants?
Q 34 What do you mean by Chemotropism?
Q 35 Where are Cytokinins present in plants?
Q 36 Give an example of a slow growth independent response in plants.
Q 37 How is information transferred from one cell to another during a growth dependent response in plants?
Q 38 Where is auxin synthesized in the plants?
Q 39 Plants do not have nerves. Do they use electrochemical signals?
Q 40 Describe an activity to show that roots are negatively phototropic.
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8. How do Organisms Reproduce?
Q 1 What type of reproduction involves gametes?
Mark (1)
Q 2 How does the embryo get nourishment inside the mother‟s body?
Mark (1)
Q 3 If a woman is using copper-T will it help in protecting her from sexually transmitted disease?
Mark (1)
Q 4 How does the asexual mode of reproduction take place in yeast?
Mark (1)
Q 5 Name the parts of female reproductive system in human beings.
Mark (1)
Q 6 Name the parts of a stamen.
Mark (1)
Q 7 Write any one method to avoid pregnancy in human beings.
Mark (1)
Q 8 Where does fertilization take place in human female?
Mark (1)
Q 9 How many individuals are involved in sexual reproduction?
Mark (1)
Q 10 Name the mode of reproduction in which new generation is created by a single parent.
Mark (1)
Q 11 What are the parts of pistil in a flower?
Mark (1)
Q 12 Write full form of DNA
Mark (1)
Q 13 Name any one organism showing process of regeneration.
Mark (1)
Q 14 What could be the reasons for adopting contraceptive methods?
Mark (1)
Q 15 Why is DNA copying an essential part of the process of reproduction? Marks (2)
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Q 16 How is the process of pollination different from fertilization?
Marks (2)
Q 17 What is the role of the seminal vesicles and the prostrate gland?
Marks (2)
Q 18 What are the changes seen in the girls at the time of puberty?
Marks (2)
Q 19 What are advantages of sexual reproduction over asexual reproduction?
Marks (2)
Q 20 What are the functions performed by the testis in human beings?
Marks (2)
Q 21 Name the different methods of contraception?
Marks (2)
Q 22 How does reproduction help in providing stability to populations of species?
Marks (2)
Q 23 How does the mode of reproduction different in unicellular and multicellular organisms?
Marks (2)
Q 24 Write down two benefits of vegetative propagation.
Marks (2)
Q 25 State the mode of reproduction for the following reproductive structures:
Reproductive Structure
Mode of Reproduction
Testis
Bud in Hydra
Filament of Spirogyra
Spore
Marks (2)
Q 26 Interpret the fact “Variations are the important aspect of sexual reproduction”.
Marks (2)
Q 27 List the methods used for growing jasmine and rose plants?
Marks (2)
Q 28 What is the fallout of sex determination test? According to you, what is the reason that it is used inspite of being banned by the
government?
Marks (2)
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Q 29 Explain the terms, 'fission' and 'regeneration' as used in relation to reproduction.
Marks (2)
Q 30 Successful gamete transfer and fusion of gametes is essential for the most critical event in sexual reproduction.
i.
ii.
Give the technical term for the fusion of gametes.
What is formed as a result of fusion of gametes?
Marks (2)
Q 31 Differentiate between pollination and fertilisation.
Marks (2)
Q 32 State two important functions of testis.
Marks (2)
Q 33 Complete the relationship as mentioned:
Process
Site of Occurrence
Fertilisation of egg
a
b
Testis
Pollen formation
c
Synthesis of estrogen
d
Marks (2)
Q 34 Match the organisms with their mode of reproduction.
Organism
Mode of Reproduction
Plasmodium
a
b
Regeneration
Rhizopus
c
d
Vegetative propagation
Marks (2)
Q 35 Is female foeticide a matter of national concern?
Marks (2)
Q 36 How will an organism be benefited if it reproduces through spores?
Marks (3)
Q 37 Why is vegetative propagation practiced for growing some types of plants?
Marks (3)
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Q 38 What is the importance of DNA copying in reproduction?
Marks (3)
Q 39 How does binary fission differ from multiple fission?
Marks (3)
Q 40 Can you think of reasons why more complex organisms can not give rise to new individuals through regeneration?
Marks (3)
Q 41 Why is variation beneficial to the species but not necessarily for the individual?
Marks (3)
Q 42 What is menstruation?
Marks (3)
Q 43 Show by figures only the asexual mode of reproduction by budding in case of Hydra.
Marks (3)
Q 44 How does the vegetative reproduction take place in Bryophyllum?
Marks (3)
Q 45 Draw and label longitudinal section of a flower.
Marks (3)
Q 46 Manu after his fourteenth birthday got noticeable change in his voice. Solve this mystery. Write down four more changes related
to this age in males.
Marks (3)
Q 47 Describe any three modes of asexual reproduction in unicellular organisms along with examples.
Marks (3)
Q 48 What are sexually transmitted diseases? Name four such diseases. Name the disease which damages the immune system of
human body.
Marks (3)
Q 49 (a) Explain the terms
(i) Implantation
(ii) placenta
(b) What is the average duration of human pregnancy?
Marks (3)
Q 50 Label the following structures in the human female reproductive system:
a) Fallopian tube
b) Uterus
c) Cervix
d) Ovary
e) Vagina
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f) Lining where the foetus is implanted
Marks (3)
Q 51 Label the parts in a bisexual flower which forms the
a) Carpel
b) Stamen
Marks (3)
Q 52 What happens when the egg is not fertilised in an adult human female?
Marks (3)
Q 53 Draw and label the figure showing germination of pollen on stigma.
Marks (5)
Q 54 Draw and label the diagram of human female reproductive system. Marks (5)
Q 55 (A) Illustrate with a diagram the process of reproduction which takes place in Plasmodium.
(B) Write down the points of difference between asexual reproduction taking place between amoeba and the above given organism.
Marks (5)
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Q 56 (A) “Contraceptive methods prove to be a boon to the society”. Explain the fact.
(B) Write down two differences between tubectomy and vasectomy.
Marks (5)
Q 57 (A) “Fertilization is a stepwise process in plants”. Demonstrate with the help of a diagram.
(B) Give the technical terms involved in the fusion of different types of cells at the end of the process.
Marks (5)
Q 58 (a) Name one organ each in female and male reproductive system which play a role of endocrine gland along with production of
germ cells. Name one hormone secreted by each of them.
(b) State two advantages of development of the embryo in the mother‟s womb.
(c) Where does fertilisation occur in case of human female and name the place where fertilized egg gets implanted.
Marks (5)
Q 59 (I) Give two reasons of avoiding frequent pregnancies by women.
(II) Explain the following methods of contraception giving one example of each:
a) Barrier method b) Chemical method c) Surgical method.
Marks (5)
Q 60 Draw L.S. of a flower and label the part that (i) produces pollen grain. (ii) transfers male gametes to the female gametes.
(iii) is sticky to capture the pollen grain.(iv) develops into a fruit.
Marks (5)
Q 61 (a) Explain the importance of placenta in the development of human embryo.
(b) Give illustration of two sexually transmitted diseases each, transmitted by bacteria and viruses.
(c) What according to you is the most effective contraceptive to prevent spread of such diseases?
Marks (5)
Q 62 (a) Give an example of a bisexual flower. What is its female reproductive part known as?
(b) Draw a diagram of its longitudinal section showing the process of germination of pollen on stigma and label the following on it:
(i) Male germ cell (ii) female germ cell (iii) Ovary (iv) pollen tube
(c) Pollination may occur without fertilisation but fertilisation will not take place without pollination. Give reason. Marks (5)
Q 63 a) What is the basic advantages of sexual reproduction over asexual reproduction?
b) List the parts of a stamen.c) Draw and label the parts of female reproductive system in human beings. Marks (5)
Q 64 a) Name the category of diseases caused by sexual contact.
b) Cite the names of two bacterial and two viral STD‟s.
c) Is there any way of to prevent such diseases?
Marks (5)
Q 65 a) Mention three ways of preventing unwanted pregnancy.
b) Which method would a couple follow after completing their family? Why?
Marks (5)
Q 66 Write the functions of any five amongst the following.
(i) Uterus (ii) Copper T (iii) Seminal vesicles (iv) Urethra(v) Spore formation (vi) Stamen (vii) Carpels Marks (5)
Q 67 a) Which organ is responsible for nourishing the embryo?
b) Describe its structure briefly.
c) Give its two functions.
Marks (5)
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Most Important Questions
Q 1 What are the characteristics of the flowers pollinated by insects?
Q 2 What are the advantages of using plant tissue culture for propagation?
Q 3 What is double fertilization?
Q 4 What is vegetative propagation?
Q 5 Give some examples of vegetatively propagated plants.
Q 6 Differentiate between monoecious and dioeceous plants.
Q 7 What is the basic source for transfer of information from one generation to another generation?
Q 8 Write some account on the importance of DNA copying in reproduction.
Q 9 Name the organisms in which binary fission and multiple fission occur.
Q 10 How is reproduction in an individual achieved from a single cell type, if the organism itself consists of many cell types?
Q 11 Name a plant in which bud development takes place at leaf margins.
Q 12 What is tissue culture?
Q 13 Define pollination.
Q 14 How is the process of pollination different from fertilisation?
Q 15 What is the advantage of sexual reproduction over asexual reproduction?
Q 16 Which part of the flower get converted into seed and fruit after fertilization?
Q 17 What are the different parts of the embryo which form leaf, stem and root in the plant?
Q 18 What are the male and female sex organs in plants?
Q 19 Give the function of scrotum.
Q 20 What are the male and female gametes called?
Q 21 Name the part of the female genital tract where foetus develops?
Q 22 Where are the sperms stored in male?
Q 23 When do boys and girls attain puberty?
Q 24 Define adolescence.
Q 25 What are the sex hormones in males and females?
Q 26 What is puberty?
Q 27 What are the primary sex organs in males and females?
Q 28 From which organ is testosterone secreted? Write the functions of testosterone.
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Q 29 What is the common passage for sperm and urine?
Q 30 Write some account on fertilsation in human beings.
Q 31 Define menstrual cycle.
Q 32 What happens if the egg is not fertilised?
Q 33 What is foetus?
Q 34 Name the part from which embryo nourishes itself during its development.
Q 35 Define reproductive health.
Q 36 Give the name of some STDs.
Q 37 What are sexually transmitted diseases?
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9. Heredity and Evolution
Q 1 Who is known as “father of genetics”?
Mark (1)
Q 2 Who isolated DNA for the very first time?
Mark (1)
Q 3 What is Mendel‟s factor better known as?
Mark (1)
Q 4 How are the two strands of DNA held together?
Mark (1)
Q 5 What are the features that Archaeopteyrx has in common to the reptiles?
Mark (1)
Q 6 What does the presence of 21st extra chromosome cause?
Mark (1)
Q 7 What is heredity?
Mark (1)
Q 8 Expand RNA
Mark (1)
Q 9 How is asexually reproducing organism capable of exhibiting hereditary characters?
Mark (1)
Q 10 Why is the decreasing number of surviving tigers a cause of worry from the point of view of genetics?
Mark (1)
Q 11 Who provided the experimental evidence to support the theory of origin of life from inanimate matter?
Mark (1)
Q 12 Write the characteristics on the basis of which duck-biled platypus is considered as a link between reptiles and mammals.
Mark (1)
Q 13 In what way are the off springs produced through sexual reproduction different from those produced by asexual reproduction?
Mark (1)
Q 14 Mendel crossed a pure white recessive pea plant with a dominant pure red flowered plant. How will be the first generation of
hybrids?
Mark (1)
Q 15 Name a vestigial organ present in the human body.
X Science C.B.S.E. Practice Paper
Mark (1)
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Q 16 Name two organisms in which sex determination is regulated by environmental factors.
Mark (1)
Q 17 When Mendel crossed a Tall plant with a dwarf plant, no medium height plants were obtained in F1 generation. Why?
Mark (1)
Q 18 Differentiate between homologous and analogous organs.
Marks (2)
Q 19 If we cut the tail of a mouse, will tail occur in the next generation of that mouse?
Marks (2)
Q 20 What do you mean by organic evolution?
Marks (2)
Q 21 Are forelimbs of man and frog analogous organs? Why or why not?
Marks (2)
Q 22 Give two functions of chromosomes.
Marks (2)
Q 23 What are vestigial organs? Give examples.
Marks (2)
Q 24 What do you mean by autosomes?
Marks (2)
Q 25 Which abnormal behavior of chromosomes cause Down‟s syndrome?
Marks (2)
Q 26 Explain Speciation. How does geographical isolation results in speciation?
Marks (2)
Q 27 Why are the traits acquired during the lifetime of an individual not inherited?
Marks (2)
Q 28 (i) What happened when Mendel crossed two traits of a character in a pea plant?
(ii) What will be the percentage of ab gametes produced by AaBb parent?
Marks (2)
Q 29 The human hand, cat paw and horse foot, when studied in detail, shows the same structure of bones and also points towards a
common origin.
i. What is the term given to such structures?
ii. What do you conclude from this?
Marks (2)
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Q 30 How can we calculate the age of a fossil?
Marks (2)
Q 31 (i) State one of the evolutionary forces that lead to the origin of a new species according to the synthetic theory of evolution.
(ii) What is the evolutionary significance of Archaeopteryx?
Marks (2)
Q 32 a) Arrange the following according to their evolutionary closeness: Broccoli, cauliflower, wild cabbage, cabbage.
b) Whose DNA among the above do you think is most similar to that of humans.
Marks (2)
Q 33 What are fossils? Of what interest are fossils to the evolutionary biologists?
Marks (2)
Q 34 Define
(i) Variation
(ii) Fossils
(iii) Gene.
Marks (3)
Q 35 What evidence does fossil provide about our evolution?
Marks (3)
Q 36 What is the basic structural unit of a DNA? What are its components?
Marks (3)
Q 37 What is Mendel‟s contribution to heredity and evolution?
Marks (3)
Q 38 How does the mechanism of heredity work?
Marks (3)
Q 39 (a) State one of the evolutionary forces leading to the origin of a new species according to the synthetic theory of evolution.
(b)
What is the effect of DNA copying which is not accurate on the reproduction process?
(c) What is a chromosome?
Marks (3)
Q 40 Who gave the concept of Natural selection? How does the process of natural selection relate to organic evolution?
Marks (3)
Q 41 Explain the method of sex determination in humans.
Marks (3)
Q 42 (a) Explain the term acquired traits?
(b) “Acquired traits are not capable of directing evolution.” Justify the statement by giving atleast two reasons.
Marks (3)
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Q 43 (a) What is the function of genes in an organism?
(b) Who proposed the theory of natural selection? Why was this theory criticized?
Marks (3)
Q 44 (a) If we cut the tail of a mouse, will tail occur in the next generation of that mouse? Give reason to support your answer.
(b)
What are the features that Archaeopteyrx had in common to the reptiles?
Marks (3)
Q 45 (a) Explain analogous organs and homologous organs.
(b) Identify the analogous and homologous organs amongst the following
wings of an insect, wings of a bat, forelimbs of frog, forelimbs of a human.
Marks (3)
Q 46 “Theory of Natural Selection” was proposed by which scientist? Explain this theory briefly.
Marks (3)
Q 47 (a) Expand the term „DNA‟.
(b) Name the part of the cell where it is located?
(c) Explain its utility in the process of reproduction of the cell.
Marks (3)
Q 48 (a) Name the scientist who isolated DNA for the very first time?
(b)
Define
(i) Variation
(ii) Gene
Marks (3)
Q 49 We have 23 pairs of chromosomes but still numerous characters are found in humans. How can we justify this?
Marks (3)
Q 50 Demonstrate with an example that traits may be dominant or recessive. Write down Mendel‟s law related to it.
Marks (3)
Q 51 (A) Give the common features that we share with other vertebrates at embryonic stage.
(B) Give its importance in study of evolution.
(C) Name any other field of study which supports the evolutionary relationship.
Marks (3)
Q 52 (i) Why human males are called heterogametic?
(ii) Explain how the sex of a child is determined at the time of conception in human beings.
Marks (3)
Q 53 What are the causes of variations in the clones?
Marks (3)
Q 54 Is it true to say that evolution is progressive from lower forms to higher forms. Justify.
Marks (3)
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Q 55 In human beings, blue eye colour is recessive to brown eye colour. If a brown eyed man has a blue eyed mother, then find:
a) What are the possible genotypes of his father?
b) What is the genotype of the man and his mother?
Marks (3)
Q 56 Guinea pig having black colour, when crossed with guinea pig having same colour, produced 100 offsprings, out of which 80
were black and 20 were white. Find out:
a) What is the possible genotype of the guinea pigs?
b) Which trait is dominant and which trait is recessive?
c) What is the cross called as and what is its phenotypic ratio?
Marks (3)
Q 57 Distinguish between acquired and inherited traits, giving one example of each.
Marks (3)
Q 58 Differentiate between
(i) DNA and RNA
(ii) Chromosome and chromatin.
Marks (5)
Q 59 What is Darwin‟s theory of evolution?
Marks (5)
Q 60 (a) Define heredity. What is the physical basis of heredity?
(b) What are the phenotypic and genotypic ratios in the F2 generation in monohybrid cross?
(c) A boy has parents with two different hair colors: one with red hair and the other with black hair. The boy has black hair. If we
consider the black colour dominating over the red colour, what could be the possible genotypes of the boy?
Marks (5)
Q 61 The genotype of green stemmed tomato plants is denoted as GG and that of purple stemmed tomato plants as gg. When these
two are crossed:
(a) What colour of stem would you expect in their F1 progeny?
(b) Give the percentage of purple stemmed plants if F1 plants are self pollinated.
(c) In what ratio would you find the genotypes GG and Gg in the F2 progeny?
Marks (5)
Q 62 a. Give the common name of the plant on which Mendel performed his experiments.
b. Why did Mendel use the term factors and what are these factors called now?
c. What are genes? Where are the genes located?
Marks (5)
Q 63 How did Mendel prove that traits are inherited independently?
Marks (5)
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Most Important Questions
Q 1 An elephant learns a trick at the circus. Will his children also know the trick by birth? Support your answer with reasons.
Q 2 What are the chances of having a baby boy in a marriage between a man with blood group O and a woman with blood group AB?
Give reasons.
Q 3 If your mother has pierced ears, will you inherit the trait? If not why?
Q 4 How does variation lead to evolution?
Q 5 How can you say that more the similarity in characters, more recent is the ancestry of two organisms?
Q 6 Do you think adaptations can bring about evolution? How?
Q 7 Why cannot two organisms having different DNA content mate among themselves?
Q 8 Give one most important criteria to differentiate a new species from its mother population.
Q 9 Why cannot random variations bring about steady evolution?
Q 10 Can you justify the statement that „human males are responsible for determining the sex of the baby and not females‟?
Q 11 What is natural selection? How can it help an organism to be „selected‟?
Q 12 How can you say that in Mendel‟s monohybrid cross the F2 dominants are not all same?
Q 13 Differentiate between inherited and acquired traits. Give examples.
Q 14 How do genes express themselves in organisms?
Q 15 What is heredity? What is the F2 phenotypic ratio in Mendel‟s dihybrid cross? Can you explain heredity with this cross?
Q 16 How can we say that there is no „progress‟ in the concept of evolution?
Q 17 Two organs perform a same function but have different origins. What are they called?
Q 18 Where in the world did human beings originate and in what form?
Q 19 What are missing links? How do they help in tracing evolution?
Q 20 Name the method to determine the age of a fossil.
Q 21 How do layers of fossils form under earth?
Q 22 How are wings of a sparrow and flippers of a whale related?
Q 23 How can you say that an African native, an Australian native, a Maori tribe and a Punjabi guy all belong to the same species?
Q 24 How and why did human race spread from Africa to other parts of the world?
Q 25 How do fossils help in studying evolution? Q 26 Name any three organs homologous to human hands.
Q 27 What do you understand by evidences of evolution? Give three examples.
Q 28 How can we say that change in genes can be brought about by change in DNA?
Q 29 How does a gene express itself in a cell? Q 30 What is excavation and how is it related to study of evolution?
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10.Light- Reflection and Refraction
Q 1 Define reflection of light.
Mark (1)
Q 2 Light enters from air to water having refraction index 1.33. What is the speed of light in the water? The speed of light in vacuum
is 3 x 108 ms-1.
Mark (1)
Q 3 Find the focal length of a convex mirror where radius of curvature is 32 cm.
Mark (1)
Q 4 A boy has a tatto made on his left hand . On which hand will tatto appear in image , seen in the plane mirror?
Mark (1)
Q 5 For which colour the refractive index of material is maximum?
Mark (1)
Q 6 Complete the path ray of light after reflection in the given ray diagram.
Mark (1)
Q 7 What happens to the light when it travels from denser to rarer medium?
Mark (1)
Q 8 Can an enlarged image be formed by a convex mirror?
Mark (1)
Q 9 Where will the image will be formed ,when an object is placed at the focus of a concave lens?
Mark (1)
Q 10 Can total internal reflection take place when light travels from rarer to denser medium?
Mark (1)
Q 11 Will there be any change in the focal length of concave mirror when it is dipped in water?
Mark (1)
Q 12 The refractive index of diamond is 2.42. What is the meaning of this statement?
Marks (2)
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Q 13 What do you understand by the principal focus of a concave mirror?
Marks (2)
Q 14 Why do we prefer a convex mirror as a rear-view mirror in vehicles
Marks (2)
Q 15 A doctor has prescribed a corrective lens of power + 2.0 D. Find the focal length of the lens.
Marks (2)
Q 16 (a)What is the nature of a lens of focal length?
(b)Find the power of the lens .
Marks (2)
Q 17 Where and what is the nature of image formed by a convex lens , when object is placed at infinity ?
Marks (2)
Q 18 Where and what type of image will be formed when an object is placed between the pole and principal focus point of the
concave mirror?
Marks (2)
Q 19 The magnification “m” for a mirror is +1. What does this signify?
Marks (2)
Q 20 State two uses each of concave mirror and convex mirror.
Marks (2)
Q 21 Why do we prefer a convex mirror as a rear-view mirror in vehicles?
Marks (2)
Q 22 What are the uses of a concave mirror?
Marks (3)
Q 23 What is the difference between real and virtual images?
Marks (3)
Q 24 Define the refraction of light. State the two laws of refraction.
Marks (3)
Q 25 If light passes from one medium to another medium, what will happen to its frequency and wavelength?
How can we identify that whether a given piece of glass is a convex lens, concave lens or a plane glass piece?
Marks (3)
Q 26 If the speed of light in air is 3 × 108 m/s, then calculate the speed of light in glycerine which has refractive index of 1.47. What
is the physical significance of refractive index?
Marks (3)
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Q 27 An object is placed 3 m away from a lens which forms its image at a distance of 1 m on the same side of the lens where the
object is placed. Find the power of the lens. What is the type of lens used?
Marks (3)
Q 28 Write Snell‟s law. Light enters from air to glass having refraction index 1.50. What is the speed of light in the glass? The speed
of light in vacuum is 3
108 ms-1.
Marks (3)
Q 29 A convex lens forms a real image of a point object placed on its principal axis. What will happen to the image if the upper half of
lens is painted black? Will its position be shifted?
Marks (3)
Q 30 A spherical mirror forms an erect image three times the size of the object. If the sum of the image and the object distance is 100
cm, find the focal length.
Marks (3)
Q 31 A combination of lenses is made by putting a convex lens of focal length 15 cm in contact with a concave lens of focal length 20
cm in such a way that they have common principal axis. What will be the resulting nature of the combination and what will be its focal
length?
Marks (3)
Q 32 Find the focal length of a plane mirror with the help of mirror formula. Explain the power of a plane mirror.
Marks (3)
Q 33 A beam of light is directed towards a sheet of crown glass (refractive index = 1.52) at an angle of 45º. At what angle will the
beam be refracted?
Marks (3)
Q 34 In which direction will the ray of light bend, with respect to the normal, when it travels from
1. rarer medium to a denser medium.
2. denser medium to a rarer medium.
o
A beam of light is directed towards a sheet of crown glass (refractive index =1.52) at an angle of 45 . At what angle will the beam be
refracted?
Marks (3)
Q 35 Give reasons for the following.
1. A concave mirror, used as a head mirror by an ENT specialist, can be used as a shaving mirror.
2. A ray of light passing through the centre of curvature of a spherical mirror retraces its path on reflection from the mirror.
Marks (3)
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Q 36 Mansi took a safety-pin of length 3 cm and placed it upright at a distance of 15 cm from a convex lens of focal length of 10 cm.
What can you say about the image formed?
Marks (3)
Q 37 An object is placed at a distance of 10cm from a convex mirror of focal length 15 cm. Find the position and nature of the image.
Marks (5)
Q 38 An object 5 cm in length is held 25 cm away from a converging lens of focal length 10cm. Draw the ray diagram and find the
position, size and nature of the image formed. Marks (5)
Q 39 An object is placed at 10cm in front of a concave mirror of focal length 15cm. Find the position, nature and size of the image.
Marks (5)
Q 40 The image of an object placed at the centre of curvature of a lens will be formed at the same distance from the lens on the other
side and that its size is the same as the object. Identify the lens and prove the statement.Marks (5)
Q 41 An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the
position, size and nature of the image formed.
Marks (5)
Q 42 An object is placed in front of a convex lens at a distance of
where „f‟ is the magnitude of the focal length of the lens.
Prove that the magnification produced by the lens is „n‟. Also
find the two values of the object distances for which a convex lens of power 2.5 D will produce an image that is four times as large as
the object. Marks (5)
Q 43 What is a converging lens? How will you find the focus of a converging lens? A 5.0 cm long pin is held perpendicular to the
principal axis of a convex lens of focal length 10 cm. The distance of the pin from the lens is 15 cm. At what distance from the lens
image will be formed? What will be the size of the image? Marks (5)
Q 44 What do you understand by the power of a lens?
An object is placed 3 m away from a lens which forms its image at a distance of 1 m on the same side of the lens where the object is
placed. Find the power of the lens. What is the type of the lens used?
Marks (5)
Q 45 Explain and show the converging action of a convex lens on a parallel beam of light and diverging action of a concave lens on a
parallel beam of light.
Marks (5)
Q 46 Write down the New Cartesian Sign Conventions for lenses.
Marks (5)
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Most Important Questions
Q 1 Name the form of energy which enables us to see the objects?
Q 2 What types of waves are light waves?
Q 3 Where will the image be formed when the object is placed between the infinity and pole of the convex mirror?
Q 4 A convex mirror used on a truck has 3m radius of curvature. If a bus is located at 5m from this mirror, find the position, nature
and size of the image.
Q 5 Which kind of mirror has
(i) Positive focal length
(ii) Negative focal length?
Q 6 An object of size 5cm is placed at a distance of 25cm from the pole of a concave mirror of radius of curvature 30cm. Calculate the
distance and size of the image formed. What will be the nature of the image?
Q 7 An object is placed 20cm in front of mirrors M 1 and M2 separately and image is found to be formed at a distance of 15 cm in front
of it in case of M1 and behind it in case of M2. Find the focal length and kind of mirror in each case.
Q 8 Give two differences between real and virtual images.
Q 9 Write mirror formula for a concave mirror.
Q 10 Find the size, nature and position of the image formed when an object of size 1 cm is placed at a distance of 15cm from a
concave mirror of focal length 10cm.
Q 11 An object 2 cm is placed at a distance of 16cm from a concave mirror which produces a real image 3 cm high.
i. What is the focal length of the mirror.
ii. Find the position of the image.
Q 12 An object is placed at a distance of 10cm from a concave mirror of focal length 20cm.
i.
Draw a ray diagram for the formation of image.
ii.
Calculate the image distance.
iii.
State two characteristic of image formed.
Q 13 An object 5 cm high is placed at a distance of 10 cm from a convex mirror of radius of curvature 30 cm. Find the nature, position
and size of the image.
Q 14 Which mirror always produces a virtual, erect and diminished image of an object?
Q 15 One want to see an enlarged image of an object in a mirror. What type of mirror should one use?
Q 16 If the magnification of a body of size 1m is 2, what is the size of the image?
Q 17 What is the relation between the focal length and radius of curvature in case of a Concave mirror? If the radius of a curvature of
a concave mirror is 36cm, what is the focal length?
Q 18 With respect to air the refractive index of ice and that of rock salt are 1.31 and 1.54 respectively. Calculate the refractive index of
rock salt with respect to ice.
Q 19 With respect to air the refractive index of water and that of benzene are 1.33 and 1.50 respectively. Calculate the refractive index
of benzene with respect to water.
Q 20 Wavelength of radiation 850nm falls on a surface. Will this surface be visible or not? Explain.
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Q 21 An object of size 3cm is placed at a distance of 15cm from a convex lens of local length 10cm. Calculate the distance and size
of the image so formed.
Q 22 Light enters from air to water having refractive index 1.50. What is the speed of light in water if the speed of light in air is 3
108 m/s?
Q 23 What is dispersion? Which color of light deviates most on passing through a prism? When two prisms are placed together with
one inverted and white light is passed through this combination, what will be the result?
Q 24 How does a rainbow forms?
Q 25 Why do blue and yellow pigments give green colour on mixing?
Q 26 What are the values for the angle of incidence and angle of reflection for normal incidence?
Q 27 What is the relation between the critical angle and the refractive index for a medium?
Q 28 Write the expression for lens formula for a convex lens.
Q 29 What is the critical angle of incidence? Prove Q 30 What is the magnification obtainable by simple microscope?
Q 31 What is the S.I unit of power of lens? A convex lens has a focal length of 50cm. Calculate its power.
Q 32 Find the focal length of a concave lens of power –2D.
Q 33 How does a convex lens behave as a magnifier? Find the magnification of this lens and suggest a method to improve
magnification.
Q 34 Write the relation between the power and focal length. What are the sign conventions for mirrors.
Q 35 An object is placed at a distance of 10cm from a concave lens of focal length 20cm. i. Draw a ray diagram for the formation of
image.
ii. Calculate the image distance. iii. State two characteristic of image formed.
Q 36 If the image formed by a convex lens is of the same size as that of the object, what is the position of the image with respect to the
lens?
Q 37 State with the help of the ray diagram, the formation of image of a finite object placed in front of a convex lens between f and 2f.
Give two characteristics of the image so formed.
Q 38 If an object of 7 cm height is placed at a distance of 12 cm from a convex lens of focal length 8 cm, find the position, nature,
height of the image.
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11.Human Eye and Colourful World
Q 1 What happens to the image distance in the eye when we increase the distance of an object from the eye?
Mark (1)
Q 2 Why does the sky appear dark instead of blue to an astronaut?
Mark (1)
Q 3 What do you understand by power of accommodation of the eye?
Mark (1)
Q 4 Which part of the eye causes change in the focal length of the eye lens?
Mark (1)
Q 5 In an eye, where is image formed?
Mark (1)
Q 6 Explain tyndall effect.
Mark (1)
Q 7 Where is far point located for a normal eye?
Mark (1)
Q 8 Cylindrical lenses are used to correct which type of defects of vision?
Mark (1)
Q 9 Which type of lens is used to correct Hypermetropia ?
Mark (1)
Q 10 What is the cause of cataract?
Mark (1)
Q 11 When white light travels through prism, which colour travels slowest?
Mark (1)
Q 12 What is a simple microscope?
Mark (1)
Q 13 In spectrum of white light passing through a prism ,which colour bends the least?
Mark (1)
Q 14 What happens to the image distance in the eye when we increase the distance of an object from the eye?
Mark (1)
Q 15 Name the phenomenon occurring in the nature due to dispersion of light.
X Science C.B.S.E. Practice Paper
Mark (1)
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Q 16 Why one cannot see the things clearly for some time, as soon as , the person enters a dim room from bright light ?
Marks (2)
Q 17 Why do stars twinkle?
Marks (2)
Q 18 Define dispersion and spectrum?
Marks (2)
Q 19 Define least distance of distinct vision.
What is the least distance of distinct vision for a normal adult?
Marks (2)
Q 20 A patient is unable to see distant objects clearly but can see nearby objects. The doctor told him that he is suffering from an eye
defect. Can you guess the eye defect and its remedy?
Marks (2)
Q 21 The power of a convex lens is + 2.5 D. Calculate its focal length.
Marks (2)
Q 22 A student has difficulty in reading the black board while sitting in the last row. What would be the defect the student is suffering
from? How can it be corrected?
Marks (2)
Q 23 You are asked to set up traffic lights for a railway station, which colour would you choose as the danger signal and why?
Marks (2)
Q 24 What is the cause of myopia and how it can be corrected?
Marks (2)
Q 25 Why does the sky appear black instead of blue to an astronaut?
Marks (2)
Q 26 A student looks at an aeroplane flying overhead for some time. Then he suddenly moves his eyes away from it. However, he
experiences that the image of the aeroplane was still there in his eyes for a fraction of second. He is surprised but unable to understand
the reason. Can you explain?
Marks (2)
Q 27 What is the reason that we can‟t see an object clearly if it is placed very close to our eyes?
Marks (2)
Q 28 Calculate the maximum power of accommodation of a person having normal vision.
Marks (2)
Q 29 What happens to the image distance in an eye if we increase the distance of an object from the eye?
Marks (2)
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Q 30 Parul has difficulty in watching the whiteboard while sitting in the last row. What is the eye defect she is suffering from? How
this defect can be removed?
Marks (2)
Q 31 What is presbyopia? How is it corrected?
Marks (3)
Q 32 The far point of a myopic person is 40cm in front of the eye. Determine the nature and power of the lens required to correct the
problem.
Marks (3)
Q 33 Sun is visible to us about 2 minutes before the actual sunrise and about 2 minutes after the actual sunset. Explain the reason?
Marks (3)
Q 34 A person is suffering from far-sightedness. His near point is 50 cm. How can you calculate the focal length and power of the lens
used by him if he wants to read a book placed 20 cm away?
Marks (3)
Q 35 The near point of a person suffering from far-sightedness is 60 cm. What will be the type of lens and its focal length to correct
this defect of vision? Marks (3)
Q 36 What is myopia? The far point of myopic eye is at 50 cm. Calculate the power of the lens to correct the vision. Marks (3)
Q 37 What is presbyopia? Write down the two causes of this defect. Marks (3)
Q 38 What is meant by scattering of light? What is the condition for Rayleigh scattering? Why blue light can be scattered more easily
as compared to red light? Marks (3)
Q 39 What is the cause of dispersion? Marks (3)
Q 40 Explain the statements given below.
(i) Having two eyes enable a wider field of view.
(ii) Having two eyes enable us to judge distances more accurately. Marks (3)
Q 41 What is short sightedness or myopia? What causes myopia? How is myopia corrected? Marks (5)
Q 42 Explain the reason behind the colour of the sky. Why astronauts see only darkness when they look away from the sun? Marks (5)
Q 43 Why does the colour of the sun look different at different times of a day? Explain. Marks (5)
Q 44 Explain the following.
(i) Danger signals are red.
(ii) Human eye can be treated as an optical instrument. Marks (5)
Q 45 What is far point, near point and range of vision?
The near point of a hypermetropic eye is at 75 cm from the eye. What is the power of the lens required to enable the person to clearly
read the newspaper at 25 cm away from the eye?
Marks (5)
Q 46 What do you understand by scattering of light? Write down an activity to observe the scattering of light.
Marks (5)
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Most Important Questions
Q 1 Human eye is one of the most valuable and sensitive organ that
(a) Enables us to see the wonderful world and colours around us
(b) Can identify the objects
(c) Is like a camera
(d) All of these
Q 2 Which of the following does not describe working of the human eye?
(a) The lens system forms an image on a light sensitive screen called the retina.
(b) Light enters the eye through a thin membrane called the cornea
(c) Rainbow is formed due to splitting of white light
(d) Iris is a dark muscular diaphragm that controls the size of the pupil for regulating the amount of light entering into the eye.
Q 3 Electrical signals generated by light sensitive cells of retina are sent to the brain via
(a) Motor nerves
(b) Optic nerves
(c) Sensory nerves
(d) Spinal cord
Q 4 Accommodation of a human eye is the property of
(a) The eye lens to adjust its focal length
(b) The eye to see different colours
(c) Filling the eyes with tears
(d) All of the above.
Q 5 Least distance of vision for a normal eye is
(a) 25 cm
(b) 1 m
(c) 30 cm
(d)Infinity
Q 6 The eye lens forms an ___________ and _________ image of the object on the retina
(a) Virtual and erect
(b) Real and inverted
(c) Real and erect
(d)Virtual and erect
Q 7 Light sensitive cells get activated on
(a) Illumination (b) Seeing the different colours
(c) Facing opaque objects
(d) Receiving message from the brain.
Q 8 Iris contracts the pupil
(a) In bright light
(b) To allow less light to enter
(c) In darkness
(d)Only (a) and (b).
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Q 9 Colour blindness is the name given to
(a) Inability to distinguish between colours
(b) Inability to see anything
(c) Inability to see in dark
(d)Inability to see in bright light.
Q 10 Ciliary muscles help in seeing nearby and far off objects clearly by
(a) Modifying the curvature of eye lens
(b) Relaxing to make the lens thin, thus increasing its focal length
(c) Contraction to make the lens thick, thus reducing its focal length
(d)All of these.
Q 11 A person is not able to see near objects clearly, because
(a) Image is formed behind the retina
(b) Focal length of the eye lens is too great
(c) Use of convex lens has been ignored, though it was advised
(d)All of the above.
Q 12 A person is not able to see distant objects clearly, because
(a) He is suffering from myopia
(b) The defect can be rectified by using a concave lens
(c) Focal length of the eye lens is too less
(d)All of the above
Q 13 Cataract is a condition
(a) When the crystalline lens becomes milky and cloudy
(b) That may cause partial or complete loss of vision
(c) That can be rectified through a cataract surgery
(d)All of these.
Q 14 Hypermetropia is also known as far sightedness because
(a) The person is not able to see clearly the distant objects, but can see near objects clearly
(b) The person is able to see clearly the distant objects, but not near objects
(c) The person is not able to see clearly the distant or near objects
(d)The person is able to see clearly the distant or near objects.
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Q 15 Presbyopia can be corrected by
(a) Using bifocal lenses
(b) Using microscopes
(c) Using binoculars
(d)Using sunglasses
Q 16 What do you understand by power of accommodation of the eye?
Q 17 Define least distance of distinct vision.
Q 18 Why does it take some time to see objects in a dim room when you enter the room from bright sunlight outside?
Q 19 The far point of a myopic person is 80cm in front of the eye. What is the nature and power of the lens required to correct the
problem?
Q 20 What is short sightedness or myopia? What causes myopia? How is myopia corrected?
Q 21 What is presbyopia? How is it corrected?
Q 22 The shape of the triangular prism:
(a) Makes the emergent ray bend at angle to the direction of the incident ray
(b) Angle of deviation is the angle between the incident ray produced and the emergent ray produced
(c) Both (a) and (b)
(d)Neither (a) nor (b).
Q 23 Splitting of white light on passage through a triangular prism
(a) Takes place due to the inclined surfaces
(b) Is known as dispersion of light
(c) Is into a band of seven colours known as spectrum
(d)All of these.
Q 24 Dispersion of white light takes place because:
(a) Different colours of light bend through different angles with the incident ray
(b) The red light bends the least and the violet light bends the most
(c) Both (a) and (b)
(d)Refractive index of glass is not uniform in the prism.
Q 25 Placement of another identical prism in an inverted position with respect to the first and allowing the colours of spectrum to pass
through it will:
(a) Change the spectrum into white light
(b) Change the spectrum into a black band
(c) Keep the spectrum as before
(d) Split into more colours.
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Q 26 Atmospheric refraction occurs because:
(a) Light is traveling through vacuum and air
(b) Refractive index of atmosphere keeps changing because its physical conditions do not remain same
(c) Neither (a) nor (b)
(d)Both (a) and (b).
Q 27 Twinkling of a star is due to
(a) Atmospheric refraction of sunlight(b) Atmospheric refraction of starlight(c) Lightening in the sky(d)None of these.
Q 28 The path of light passing through a clear solution is not visible, but becomes visible through a colloid:
(a) Because light is scattered by relatively larger particles(b) Because light is getting refracted
(c) Because light is getting refracted as well reflected(d)All of these.
Q 29 Which one of the following is the correct option?
(a) Size of scattering particles – Dispersion of light (b) Very fine scattering particles – Blue light gets scattered
(c) Large scattering particles – No dispersion or scattering of light (d)Opaque particles – Tyndall effect.
Q 30 The sky appears blue because
(a) Molecules of air and other particles in the atmosphere are smaller than wavelength of visible light
(b) Light of shorter wavelengths at the blue end are scattered more than the red light whose wavelength is 1.8 times
(c) The scattered blue light enters our eyes (d)All of these.
Q 31„Danger‟ signal lights are usually red in colour because
(a) It is a bright colour
(b) It least scattered by fog or smoke
(c) It has smaller wavelength and can be seen from a distance (d)All of these.
Q 32 Why do stars twinkle? Q 33 Define dispersion-- What is spectrum?
Q 34 How will you say that white light of the sun is made of seven colours?
Q 35 Why does the sun appear reddish early in the morning?
Q 36 What happens to the image distance in the eye when we increase the distance of an object from the eye?
Q 37 Why does the sky appear dark instead of blue to an astronaut? Q 38 What do you mean by extended spectrum?
Q 39 How will you distinguish between pure and impure spectrum?
Q 40 Complete the ray diagram as shown in the figure.
What is the net deviation produced in this case?
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12.Electricity
Q 1 How much current will an electric heater coil draw from a 220 volt line, if the resistance of the heater coil is 40
?
Mark (1)
Q 2 What is electric current?
Mark (1)
Q 3 What is the SI unit of electric current?
Mark (1)
Q 4 What is the SI unit of electric charge?
Mark (1)
Q 5 Which metal is the best conductor of electricity at room temperature?
Mark (1)
Q 6 Metals conduct electricity. Why?
Mark (1)
Q 7 How should the resistances be connected so that the equivalent resistance is increased?
Mark (1)
Q 8 The length of the wire is doubled, what is the change in its resistivity?
Mark (1)
Q 9 The combination of resistances shown below has equivalent resistance equal to 12 ohm, what is the value of R?
Mark (1)
Q 10 Why is tungsten metal used for making the filaments of electric bulbs?
Mark (1)
Q 11 There is change in the length of the wire. Will the wire's resistance change?
Mark (1)
Q 12 What is the power of an electric lamp, if it draws 20 A current when connected to 220 V line?
Mark (1)
Q 13 Calculate the number of electrons constituting one coulomb of charge. Marks (2)
Q 14 Calculate the amount of charge that would flow in 1 hour through the elements of an electric bulb drawing a current of 0.4 A.
Marks (2)
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Q 15 How much voltage should be applied to a 50
resistance , to produce 1000 J of heat in 10 seconds?
Marks (2)
Q 16 In the circuit diagram given below, find the equivalent resistances and total current flowing through the circuit.
Marks (2)
Q 17 What is resistance? In the given graph, which wire has more resistance, A or B?
Marks (2)
Q 18 In households, most electrical devices are connected in parallel combination in electrical circuits. Why is it so?
Marks (2)
Q 19 A wire is of length L. Suppose a person doubles the length of the wire without changing its cross-sectional area, what will
happen to the resistance and resistivity of the wire?
Marks (2)
Q 20 Tungsten filament of the bulb does not melt even after glowing for a long period of time. Why?
Marks (2)
Q 21 How does a fuse wire melt?
Marks (2)
X Science C.B.S.E. Practice Paper
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Q 22 When a geyser is switched on, instantly the light from the bulbs in the house gets dimmer for a moment. Why?
Marks (2)
Q 23 State Ohm‟s law. Give its mathematical expression.
Marks (3)
Q 24 Six resistors, each of 3 are connected as shown in the figure below.
Calculate the resistance between:
(a)Points P and Q.
(b)Points Xand Y.
Marks (3)
Q 25 The potential difference between the terminals of an electric heater is 30 volts when it draws current of 4 A from the source.
What current will the heater draw if the potential difference is increased to 120 volts?
Marks (3)
Q 26 A current of 4 A exists in a 10
resistor for 4 minutes. Find the charge and the number of electrons that pass through any
cross-section of the resistor in this time.
Marks (3)
Q 27 A 100 watt electric bulb is lighted for 2 hours daily and four 40 watt bulbs are lighted for 4 hours daily. Calculate the electric
energy consumed in kWh in 30 days.
Marks (3)
X Science C.B.S.E. Practice Paper
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Q 28 Two bulbs, one rated 100 W at 220 volts and the other 60W at 220 volts are connected in parallel to a 220 V supply. What
current is drawn from the supply line?
Marks (3)
Q 29 There is a uniform wire of resistance R. A person cuts it into three equal pieces and joins them in parallel. Find whether the
resistance of the combination is more or less than the resistance of the original wire.
Marks (3)
Q 30 During an activity in the school, the teacher provides a V volt battery each to Navin and Priya and also gives two identical
resistors of resistance R to each of them. Navin connects them in series with the battery, while Priya connects them in parallel with the
battery. Discuss the heat produced in time „t‟ seconds in these two cases.
Marks (3)
Q 31 A person connected two bulbs of 100 W and 60 W in parallel to a 220 V supply. Determine the current drawn from the supply
line.
Marks (3)
Q 32 Find the equivalent resistance of the given network of resistors.
Marks (3)
Q 33 (a)State the law, which relates the current in a conductor to the potential difference across its ends.
(b) Draw the V-I graphs for a
(i) Metallic conductor.
(ii) Liquid Electrolyte.
(iii) Vacuum tube.
c) A simple electric circuit has 24 V battery and a resistor of 30 ohm. What will be the current in the circuit.
Marks (5)
X Science C.B.S.E. Practice Paper
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Most Important Questions
Q 1 What is electric current?
Q 2 What is the SI unit of electric current?
Q 3 Why are metals able to conduct electricity?
Q 4 The length of the wire is doubled, what is the change in its resistivity?
Q 5 There is change in the length of the wire, will its resistance change?
Q 6 What is the SI unit of electric charge?
Q 7 Which metal is the best conductor of electricity at room temperature?
Q 8 What is ohm‟s law? Give its mathematical expression?
Q 9 Calculate the number of electrons constituting one coulomb of charge.
Q 10 Calculate the amount of charge that would flow in 1 hour through the elements of an electric bulb drawing a current of 0.4 A.
Q 11 The potential difference between the terminals of an electric heater is 30 volt when it draws current of 4 A from the source. What
current will the heater draw if the potential difference is increased to 120 volt?
Q 12 A current of 4 A exists in a 10
resistor for 4 minute. Find the charge and the number of electrons that pass through any
cross-section of the resistor in this time.
Q 13 a) State the law, which relates the current in a conductor to the potential difference across its ends.
b) Draw the V-I graphs for a
(i) Metallic conductor.
(ii) Liquid Electrolyte.
(iii) Vacuum tube.
c) A simple electric circuit has 24 V battery and a resistor of 30 ohm. What will be the current in the circuit.
Q 14 Alloys are usually used in electrical heating devices because
a. Resistivity of an alloy is generally higher than that of constituent elements
b. Alloys do not oxidize readily at high temperature
c. Both (a) and (b)
d. Neither (a) nor (b)
Q 15 A wire is carrying a current. Is It charged?
Q 16 What do you mean by conventional current?
Q 17 Heat produced due to flow of current through a conductor is given by the formula
a. H = I2 R t
b. H = V I t
2
c.
H=V t/R
d. All of the above
Q 18 An „electric fuse‟ is essential in domestic circuits, because
a. It is a safety device
b. It breaks the circuit in case of overload
c.
The circuit is broken because it melts in case of short circuit
d. All of above.
X Science C.B.S.E. Practice Paper
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Q 19 The combined resistance of any number of resistances connected in series is equal to
a. The sum of individual resistances
b. The sum of reciprocals of individual resistances
c.
Product of individual resistances
d. Highest individual resistance.
Q 20 The reciprocal of the combined resistance of any number of resistances connected in parallel is equal to
a. The sum of reciprocals of individual resistances
b. Reciprocal of the product of individual resistances
c.
Reciprocal of sum of all the resistances
d. None of the above.
Q 21 When two or more resistors are connected in series,
a. The current passing through each resistor is same
b. The potential difference across each resistor is same
c.
Both of the above
d. None of the above
Q 22 When two or more resistors are connected in parallel,
a. The current passing through each resistor is same
b. The potential difference across each resistor is same
c.
Both of the above
d. None of the above
Q 23 Commercial unit of electrical energy is
a. Joules
b. Coulombs
c.
Watts
d. k W h
Q 24 Heating effect of current passing through a wire depends on
a. Length of the wire
b. Time for which current is passed
c.
Area of cross – section of the wire
d. All of the above
Q 25 Power rating of an electric appliance indicates
a. The rate of consumption of electrical energy
b. Amount of heat evolved
c.
Brightness of the light
d. Quality of the appliance
Q 26 One kilowatt hour =
a. 3.6 x 106 J
b. 3.6 kJ
c.
1000 watt
d. 3.6 x 106 calories
Q 27 What happens to the heating effect when the direction of current is reversed?
a. Cooling effect is observed
b. Amount of heat remains unchanged
c.
There will be a short circuit
d. All of the above
X Science C.B.S.E. Practice Paper
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Q 28 Alloys are usually used in electrical heating devices because
a. Resistivity of an alloy is generally higher than that of constituent elements
b. Alloys do not oxidize readily at high temperature
c.
Both (a) and (b)
d. Neither (a) nor (b)
Q 29 An electric bulb of 40W is connected to a source of 220V, the current drawn by the bulb will be
a. 0.18A
b. 18A
c.
1.8A
d. 180A
Q 30 Electrical energy consumed in lighting an electrical bulb of 60W for 5 hours =
a. 3 kWh
b. 1.08 x 106 J
c.
0.3 kWh
d. Both b. and c.
Q 31 A man has five resistors each of value 0.2 ohms. The maximum resistance he can obtain by connecting them will be
a. 0.1 ohm
b. 1.0 ohm
c.
0.04 ohm
d. 0.4 ohm
Q 32 In a circuit two resistors are connected in series, the heat produced in the 5 ohm resistor due to the current flowing through it is
10 calorie per second. The heat generated in the 4 ohm resistor is:
a. 8 cal/s
b. 3 cal/s
c.
4cal/s
d.
None of these.
Q 33 The combination of resistances shown below has equivalent resistance equal to 12 ohm, what is the value of R?
Q 34 How is power related to current and voltage?
Q 35 How much current will an electric heater coil draw from a 220 volt line, if the resistance of the heater coil is 40 ohm ?
Q 36 What is the power of an electric lamp, if it draws 20 A current when connected to 220 V line?
Q 37 A 100 watt electric bulb is lighted for 2 hours daily and four 40 watt bulbs are lighted for 4 hours daily. Calculate the electric
energy consumed in kwh in 30 days.
Q 38 Two lamps, one rated 100 W at 220 volts and the other 60W at 220 volts are connected in parallel to a 220 V supply. What
current is drawn from the supply line?
Q 39 To produce 1000 joule of heat in 10 seconds, how much voltage should be applied to 50 ohms resistance.
Q 40 In the circuit diagram given below, find the equivalent resistances and total current flowing through the circuit.
Q 41 Three resistances R1, R2 and R3 are connected in series. Give a method to find their equivalent resistance with proof.
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13.Magnetic Effects of Electric Current
Q 1 What is a magnet?
Mark (1)
Q 2 What is the SI unit of induced current?
Mark (1)
Q 3 What is the frequency of d.c current?
Mark (1)
Q 4 What is the frequency of a.c current that you use in your house?
Mark (1)
Q 5 What is magnetic field?
Mark (1)
Q 6 There is a battery operated toy, what kind of motor is being used in it?
Mark (1)
Q 7 Give two example of devices in which d.c motor is used.
Mark (1)
Q 8 Give two examples in which a.c motor is used.
Mark (1)
Q 9 What is generator?
Mark (1)
Q 10 What is motor?
Mark (1)
Q 11 What will be the frequency of an alternating current, if its direction changes after every 0.05 s?
Marks (2)
Q 12 What is the principle on which working of electric generator is based? What are its important parts?
Marks (2)
Q 13 Why two magnetic lines of force don‟t intersect each other?
Marks (2)
Q 14 Give two methods by which we can increase the strength of magnetic field produced by a circular coil carrying current?
Marks (2)
Q 15 What are the patterns of magnetic field lines inside and outside of a solenoid? What do they indicate? Marks (2)
X Science C.B.S.E. Practice Paper
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Q 16 What are the factors which govern the force experienced by a current carrying conductor placed in a uniform magnetic field
depends?
Marks (3)
Q 17 Distinguish between an electric motor and generator?
Marks (3)
Q 18 What is direct current (d.c) and alternating current (a.c).
Marks (3)
Q 19 A current of 2 A flows through a circular coil of radius of 4 cm, and has 10 turns. The coil is aligned horizontally and current
flows though the coil in clockwise direction. Find the magnitude and direction of magnetic field at the centre of the coil due to the
current.
Marks (3)
Q 20 Why mostly all electrical home appliances like refrigerator, toaster etc. are provided with a wire having green insulation?
Marks (3)
Q 21 A solenoid is 1 m long and 2 cm in diameter and has 50 turns/cm. A current of 5 A is flowing through it. Calculate the magnetic
induction:
a) Inside the solenoid.
b) At one end on the axis of solenoid.
Marks (5)
Q 22 Explain the construction and working of electric motor?
Marks (5)
Q 23 What is the principle behind the working of electric generator? Explain its working with the help of well labeled diagram.
Marks (5)
Q 24 What is an electric generator? Write its principle. How electric current is generated in hydroelectric power plant?
Marks (5)
Q 25 How can we draw magnetic field line with the help of a magnetic compass? Describe.
Marks (5)
Q 26 Describe domestic household circuit.
Marks (5)
Q 27 Describe about short circuiting and overloading in detail.
Marks (5)
Q 28 What is an electromagnet? On what factors its magnetic field depends? Mention the differences between an electromagnet and a
permanent magnet.
Marks (5)
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Most Important Questions
Q 1 Which of the following is/are the special features of magnets?
(a) They align in the North –South direction when suspended freely
(b) They have two distinct North and South poles
(c) Like poles repel each other and unlike poles attract each other
(d) All of these
Q 2 The region surrounding a magnet, in which the force of the magnet can be detected is said to have
(a) Magnetic field
(b) Electric field
(c) Magnetic poles
(d) None of these
Q 3 A straight conducting wire is placed parallel to and over a compass needle. The deflection in the needle
(a) Becomes opposite when the direction of the current is reversed
(b) Remains in the same direction even on reversing the direction of current
(c) Keeps fluctuating on passage of current in any direction
(d) Is negligible on reversing the direction of current
Q 4 At every point of a current carrying circular loop, the concentric circles representing the magnetic fields around it would become
(a) Larger and larger as we move away from the wire
(b) So large at the centre of circular loop that they look like straight lines
(c) Both (a) and (b)
(d) Neither (a) nor (b)
Q 5 What do you understand by magnetic effect of electric current?
Q 6 Fill in the blanks:
(i) Magnetic effect of current was first observed by___________.
(ii) A compass needle is a tiny magnet, with its end pointing in the _________direction.
(iii) Magnetic field is a quantity that has both _________ and ___________.
(iv) The direction of the magnetic field around a current-carrying conductor can be explained by a simple rule known as __________
rule.
Q 7 What is a magnet?
Q 8 What is magnetic field?
Q 9 What are the properties of magnetic field?
Q 10 Why two magnetic lines of forces don‟t intersect each other?
Q 11 Give two methods with which we can increase the strength of magnetic field produced by a circular coil carrying current?
Q 12 Explain Maxwell's right hand thumb rule?
Q 13 Explain Maxwell's right hand screw rule.
Q 14 What are the properties of magnetic field due to a current through a straight wire?
Q 15 Fill in the blanks:
a) The magnetic field produced by a current-carrying straight conductor depends __________ on the distance from it.
Electric current in a circular loop creates a magnetic field, which is more concentrated in the center of the loop than outside the loop.
A circular coil having n turns, produce's magnetic field n times as ______________ as that produced by a single turn.
d) The degree of closeness of the field lines shows the_____________ of the magnetic field.
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Q 16 Magnetic field produced inside a solenoid are so strong that
(a) They can be used to magnetise a magnetic material, when placed inside the coil
(b) They can be used to magnetise a magnetic material, when placed near the coil
(c) They are still not able to magnetise a magnetic material
(d) They become permanent
Q 17 Increase in number of turns of a coil in the solenoid will
(a) Have no effect on the strength of magnetic field
(b) Will add to the strength of the magnetic field
(c) Will decrease the strength of the magnetic field
(d) Will change the direction of the magnetic field.
Q 18 A current-carrying conductor when placed in a magnetic field experiences
(a) An acceleration
(b) A force
(c) Demagnetisation
(d) None of these
Q 19 Direction of the force experienced by a current-carrying conductor when placed in a magnetic field is dependant on
(a) Direction of the current alone
(b) Direction of the magnetic field alone
(c) Direction of current as well as the direction of magnetic field
(d) None of these.
Q 20 A magnetic field cannot exert any force on a
(a) Moving magnet
(b) Stationary magnet
(c) Stationary charge
(d) Moving charge
Q 21 An alpha particle is projected towards west and gets deflected towards north by a magnetic field. The direction of the magnetic
field is
(a) Towards south
(b) Towards east
(c) Downwards
(d) Upwards.
Q 22 An electric motor is a device
(a) That works on the principle described by Fleming‟s left hand rule
(b) That converts electrical energy to mechanical energy
(c) Both (a) and (b)
(d) Neither (a) nor (b)
Q 23 The direction of the induced current is given by
(a) Right Hand Thumb Rule
(b) Fleming‟s Left Hand Rule
(c) Fleming‟s Right hand Rule
(d) All of these
Q 24 Fuse is used for protecting the circuits due to
(a) Short-circuiting
(b) Overloading of circuits
(c) Faulty connections
(d) All of these
X Science C.B.S.E. Practice Paper
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Q 25 Fill in the blanks:
i. An electromagnet consists of a core of ___________ wrapped around with a coil of ________ copper wire.
ii. The field lines inside the solenoid are in the form of__________ lines.
iii. ____________ discovered that the magnet also exerts an equal and opposite force on the current-carrying conductor.
iv The direction of the force on the conductor depends upon the direction of_____________ and the direction of the______________.
Q 26 Which rule is used find the direction of the force on a conductor in a magnetic field. Explain?
Q 27 What are the factors on which the Magnetic field produced inside a solenoid depends?
Q 28 Explain the construction and working of electric motor.
Q 29 What do you mean by electromagnetic induction?
Q 30 Which rule is used to know the direction of the induced current. Explain.
Q 31 What is the principle behind the working of electric generator? Explain its working with the help of well labeled diagram.
Q 32 Fill in the blanks:
a) To give equal potential difference to each appliance, the appliances are connected__________ to each other.
b) ________________________is used in a circuit to prevent damages to the appliances and the circuit due to overloading.
c) ____________occurs in a circuit when the live wire comes into direct contact with the neutral wire.
d) Situations in which, the current in the circuit increases abruptly is called as___________.
X Science C.B.S.E. Practice Paper
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14.Sources of Energy
Q 1 What is non-renewable source of energy?
Mark (1)
Q 2 Which type of energy we use to perform our day to day work?
Mark (1)
Q 3 Can you place alcohol under the category of renewable source of energy?
Mark (1)
Q 4 Name a renewable source of energy that we can harness for the whole year non-stop??
Mark (1)
Q 5 Which component of sunlight is responsible for carrying heat?
Mark (1)
Q 6 Which material is used for making solar cell?
Mark (1)
Q 7 Name two renewable sources of energy?
Mark (1)
Q 8 Name two non-renewable sources of energy?
Mark (1)
Q 9 What is tidal energy?
Mark (1)
Q 10 Which type of biogas plant has longer life?
Mark (1)
Q 11 What is geothermal energy? When is it available?
Marks (2)
Q 12 Give two merits of solar energy.
Marks (2)
Q 13 What are the limitations of wind energy?
Marks (2)
Q 14 Why the use of dry wood is not considered as good domestic fuel?? Marks (2)
Q 15 Why one should prefer biogas instead of traditional fuels like cow dung cakes despite the fact that they are cheaper than bio gas.
Marks (2)
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Q 16 What are the advantages of nuclear energy.
Marks (3)
Q 17 Distinguish between renewable and non-renewable sources of energy. Give examples too.
Marks (3)
Q 18 What are the forms of ocean energy that can be harnessed? Give some places in our country where it can be harnessed?
Marks (3)
Q 19 State three advantages of solar cooker?
Marks (3)
Q 20 From one fission of uranium 4x10-11 J of energy is produced. Calculate the total number of fissions necessary per second to
generate a power of 20 KW.
Marks (3)
Q 21 How much energy is gained by an electron when 1 atomic mass is converted into energy? Give your answer in MeV.
Marks (3)
Q 22 What is solar cooker? Explain its working with the help of a neat & labeled diagram.
Marks (5)
Most Important Questions
Q 1 Which type of biogas plant has longer life?
Q 2 Can you place alcohol under the category of renewable source of energy?
Q 3 Name a renewable source of energy that we can harness for the whole year non-stop?
Q 4 Name two renewable sources of energy?
Q 5 Which type of energy we use to perform our day to day work?
Q 6 What are the disadvantages of fossil fuel?
Q 7 What are the limitations of wind energy?
Q 8 Why the use of dry wood is not considered as good domestic fuel?
Q 9 Distinguish between renewable and non-renewable sources of energy. Give examples too.
Q 10 10 What are the advantages of using fixed type bio gas plant over the floating type plant?
Q 11 How does the electricity is produced in hydro power plants?
Q 12 Explain the working of fixed dome type bio gas plant.
Q 13 What is tidal energy?
Q 14 Which component of sunlight is responsible for carrying heat?
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Q 15 Which material is used for making solar cell?
Q 16 What is non-renewable source of energy?
Q 17 Name two non-renewable sources of energy?
Q 18 What is geothermal energy? When is it available?
Q 19 Give two merits of solar energy.
Q 20 What measures we can take to minimize hazards caused by nuclear reactors?
Q 21 What are the forms of ocean energy that can be harnessed? Give some places in our country where it can be harnessed?
Q 22 State three advantages of solar cooker?
Q 23 From one fission of uranium , 4x10-11 J of energy is produced. Calculate the total number of fissions necessary per second to
generate a power of 20 KW.
Q 24 How much energy is gained by an electron when 1 atomic mass is converted into energy? Give your answer in MeV.
Q 25 What are the advantages of nuclear energy?
Q 26 With the help of well-labeled diagram, describe the working of a solar water heater.
Q 27 What is solar cooker? Explain its working with the help of a neat & labeled diagram.
Q 28 Write the principle and working of the nuclear power plant. Draw labeled diagram of nuclear power plant.
Q 29 What do you understand by
(i)
Coolant
(ii)
Moderator
(iii)
Nuclear reactor
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15.Our Environment
Q 1 How pesticides accumulate in our body and cause harm to us?
Mark (1)
Q 2 Expand the term UNEP.
Mark (1)
Q 3 Name a pollutant which enters our body via food chain.
Mark (1)
Q 4 Name one biotic and abiotic component of nature.
Mark (1)
Q 5 Which chemical compound is responsible for the depletion of ozone layer?
Mark (1)
Q 6 Microorganisms are considered to be natural cleansing agents. Give reason.
Mark (1)
Q 7 What is smog?
Mark (1)
Q 8 Give an example of greenhouse gas.
Mark (1)
Q 9 Name the two main components of our environment.
Mark (1)
Q 10 Name the process in which a harmful chemical enters the food chain and gets concentrated at each level in the food chain.
Mark (1)
Q 11 What are energy pyramids?
Mark (1)
Q 12 Why is carbon monoxide harmful when inhaled?
Mark (1)
Q 13 Minimal usage of insecticides should be encouraged. Justify.
Mark (1)
Q 14 Give a reason to justify the statement “Microorganisms are considered to be natural cleansing agents”.
Mark (1)
Q 15 Give the composition of „smog‟?
X Science C.B.S.E. Practice Paper
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Page 91
Q 16 Name the programme that succeeded in forging an agreement to freeze CFC production at 1986 levels?
Mark (1)
Q 17 How is ozone formed?
Mark (1)
Q 18 State any two common methods by which solid wastes of urban areas are disposed off.
Mark (1)
Q 19 Identify which one of the following would have a hazardous impact if they persist in the environment for a long time:
Newspaper, vegetable peels, pesticides, waste from cattle shed.
Mark (1)
Q 20 Why food chains contain only 3 to 4 steps?
Marks (2)
Q 21 What is food chain? What forms the basis of every food chain?
Marks (2)
Q 22 What is trophic level?
Marks (2)
Q 23 What do you mean by eutrophication?
Marks (2)
Q 24 Define food web.
Marks (2)
Q 25 The flow of energy in the food chain is unidirectional. Comment.
Marks (2)
Q 26 Give the full form of the following
(i) IUCN
(ii) DDT
Marks (2)
Q 27 What do you mean by biological magnification?
Marks (2)
Q 28 How is ozone gas useful for our ecosystem?
Marks (2)
Q 29 Define the term Global Warming.
Marks (2)
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Q 30 Differentiate between point and non point sources of water pollution.
Marks (2)
Q 31 How are food chains and food web related to each other?
Marks (2)
Q 32 What is the role of ozone layer in the atmosphere?
Marks (2)
Q 33 How disposable garbage can be made eco friendly?
Marks (2)
Q 34 Which out of the following is not a matching pair. Give reasons.
Cow
Herbivore
Deer
Herbivore
Lion
Herbivore
Human
Omnivore
Marks (2)
Q 35 When a carnivore eats a herbivore, only 10% energy is transferred and the rest is lost. Where did all the remaining energy go?
Marks (2)
Q 36 (i) What does this diagram signify?
(ii) What happens when we move up in a food chain?
Marks (2)
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Q 37 What do you understand by the term „environment‟?
Marks (2)
Q 38 How have the wastes which we produce in everyday life, affected the environment?
Marks (3)
Q 39 What is water table? State some characteristics of drinking water.
Marks (3)
Q 40 Discuss briefly the main causes of soil erosion.
Marks (3)
Q 41 What is acid rain? How has acid rain affected our ecosystem?
Marks (3)
Q 42 What is an ecosystem? What are its components?
Marks (3)
Q 43 (a) When a population of animal 'X' was introduced into a grass land community, the number of lions increased while the
number of rabbits decreased. What is animal 'X'?
(b) Explain why productivity declines at each trophic level?
Marks (3)
Q 44 Which organisms help in recycling dead plants and animals? Marks (3)
Q 45 Differentiate between biodegradable and non-biodegradable pollutants. Classify the following under the above two categories:
DDT, paper, cotton cloth, plastics. Marks (3)
Q 46 (i) Identify the organisms given below and name the group to which they belong in the trophic level.
(ii) What are the functions of these organisms in nature?
X Science C.B.S.E. Practice Paper
Marks (3)
Page 94
Q 47 Schematically explain how is the release of CFC‟s harmful to humans?
Marks (3)
Q 48 Describe the flow of energy between various trophic levels of food chain.
Marks (5)
Q 49 What are the various trophic levels of the food chain? Explain with the help of an example of a food chain.
Marks (5)
Q 50 (a) Describe the formation of ozone.
(b) What are the benefits of ozone layer?
(c) Name the pollutant responsible for ozone depletion.
Marks (5)
Q 51 What would happen if ozone layer did not exist on earth?
Marks (5)
Q 52 “Flow of energy takes place in the ecosystem.”
(i) Why living organisms require energy?
(ii) Name the ultimate source of energy.
(iii) Which form of energy is taken up by the consumers?
(iv) In which form energy flows in an ecosystem?
(v) What is the direction of energy flow?
Marks (5)
Q 53 (i) Construct one food chain each for
a) Aquatic ecosystem,
b) Forest ecosystem and
c) Grassland ecosystem
(ii) Write two examples where man has interfered in ecosystem.
Marks (5)
Most Important Questions
Q 1 How is the environment defined?
Q 2 What is an ecosystem?
Q 3 What are the main components of the environment?
Q 4 What are the non-biodegradable substances?
Q 5 What are the biodegradable substances?
Q 6 How are the organisms grouped on the basis of obtaining their sustenance from the environment?
Q 7 What is food chain? What forms the basis of every food chain?
Q 8 Why do food chains contain only 3 to 4 steps?
X Science C.B.S.E. Practice Paper
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Q 9 Define food web.
Q 10 The flow of energy in the food chain is unidirectional. Comment.
Q 11 Microorganisms are considered to be natural cleansing agents. Give reason.
Q 12 What do you mean by biological magnification?
Q 13 Name any two artificial or man made ecosystem.
Q 14 Which organisms do come under the category of producers?
Q 15 What are two environmental problems, which are causing hazards?
Q 16 What is ozone?
Q 17 What are the properties of ozone that affect the human beings?
Q 18 How are the UV rays dangerous to human beings?
Q 19 How is the ozone produced in the atmosphere?
Q 20 In which year the amount of ozone in the atmosphere began to drop sharply?
Q 21 Drop in the levels of the ozone is linked to what?
Q 22 Where do the CFCS come from?
Q 23 Which programme has succeeded in forging an agreement to freeze CFC production at1986 levels?
Q 24 What has led to the generation of greater amounts of waste material?
Q 25 What could be the other reason for generating the waste nowadays?
Q 26 Why is much of waste becoming more and more non-biodegradable?
Q 27 Which layer of the earth is responsible for the production of ozone and what types of reactions go on?
Q 28 What is the term used for thinning of ozone layer?
Q 29 Why is ozone layer compared with a blanket?
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16.Management of Natural Resources
Q 1 What is pollution?
Mark (1)
Q 2 What is afforestation?
Mark (1)
Q 3 What do you mean by term N.G.O?
Mark (1)
Q 4 Name the chemical which is responsible for depletion of ozone layer?
Mark (1)
Q 5 What do you mean by the term biota?
Mark (1)
Q 6 What is water harvesting?
Mark (1)
Q 7 What is agriculture.
Mark (1)
Q 8 What is F.A.O?
Mark (1)
Q 9 What do you mean by the term effluents?
Mark (1)
Q 10 Give one example each of a natural and a man-made source of air pollution.
Marks (2)
Q 11 What are pesticides and herbicides?
Marks (2)
Q 12 What are the ill effects of ozone layer depletion?
Marks (2)
Q 13 Name two sources which are threats to our marine water?
Marks (2)
Q 14 Name the two sources of water pollution?
Marks (2)
Q 15 Give two advantages of using wind energy?
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Marks (2)
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Q 16 State any two disadvantages of burning of fossil fuels?
Marks (2)
Q 17 List any two methods for the management of fossil fuels?
Marks (2)
Q 18 (a) What do large dams guarantee us?
(b) What is the name of the canal constructed in Rajasthan.
Marks (2)
Q 19 (a) Why are coal and petroleum called fossil fuels?
(b) Name the two elements which are present both in CNG and petroleum.
Marks (2)
Q 20 “Construction of dams ensures electricity generation for a large number of villages”. State two reasons for opposition to
construction of dams inspite of this advantage.
Marks (2)
Q 21 What are the steps one may take to check soil erosion?
Marks (3)
Q 22 Distinguish between national parks and national sancturies?
Marks (3)
Q 23 What is soil erosion and its causes?
Marks (3)
Q 24 What are the sources of water pollution?
Marks (3)
Q 25 Describe the factors responsible for pollution of river ganga?
Marks (5)
Q 26 How can we control water pollution?
Marks (5)
Most Important Questions
Q 1 What is deforestation?
Q 2 What is afforestation?
Q 3 What do you mean by term N.G.O?
Q 4 Who are the various stakeholders in forests?
Q 5 What are the different purposes of stakeholders?
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Q 6 What is sustainable management?
Q 7 Why sustainable management is necessary?
Q 8 In what ways sustainable management can be done?
Q 9 In which year “Chipko movement” took place ? What is Chipko movement?
Q 10 For which community in Rajasthan wild life and forests have been the religious tenet?
Q 11 Which award is recently instituted on the name of Amrita Devi?
Q 12 What are the causes of deforestation?
Q 13 What are the various natural resources?
Q 14 What is the meaning of “3R”?
Q 15 Which plan came in existence in 1985 for the removal of wastes from Ganga river?
Q 16 What is water harvesting?
Q 17 In what way water harvesting can be done?
Q 18 What is the aim of water harvesting?
Q 19 What is the use of water harvesting?
Q 20 What are the two main techniques of rainwater harvesting?
Q 21 What are the traditional methods of rain water harvesting?
Q 22 What does large dams ensure us?
Q 23 Name a canal constructed in Rajasthan.
Q 24 Name two fossil fuels. How they are formed?
Q 25 What are the consequences of unequal distribution of water?
Q 26 In which year and country, the first oil well was drilled?
Q 27 For what purposes International and national laws regarding environment are being formulated?
Q 28 What are the disadvantages of burning of fossil fuels?
Q 29 What are the methods for the management of fossil fuels?
Q 30 How can we control water pollution?
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