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Angel International School - Manipay
1st Term Examination –November, 2016
Chemistry
Grade–11C
Duration: 2 1/2Hours
Index No:- …………
Part1
1. The letters X, Y and Z represent different atoms.
40
39
40
19X
19Y
20Z
What can be deduced from the proton numbers and nucleon numbers of X, Y and Z?
A. X and Y are the same element.
C. X has more protons than Y.
B. X and Z are the same element.
D. Z has more neutrons than Y.
2. How does a magnesium atom form a bond with an oxygen atom?
A. by giving one pair of electrons to the oxygen atom
B. by sharing one pair of electrons, both electrons provided by the magnesium atom
C. by sharing two pairs of electrons, both pairs provided by the oxygen atom
D. by sharing two pairs of electrons, each atom donating one pair of electrons
3. Which of the following contains the same number of electrons as an atom of neon?
A. Cl–
B . Li
C. Li+
D . O24. 124 g of phosphorus vapour has the same volume as 71 g of chlorine gas at the same temperature
and pressure.
What is the formula of a molecule of phosphorus?
A. P8
B. P4
C. P2
D. P
5. Substance X liberates iodine from aqueous potassium iodide
and decolourises acidified
aqueous potassium manganate(VII).
How is the behaviour of X described?
A. as an oxidising agent only
B. as an oxidising agent and a reducing agent
C. as neither an oxidising agent nor a reducing agent
D. as a reducing agent only
6. In which process is a catalyst not used?
A. The Blast furnace for the manufacture of iron.
B. The Contact process for the manufacture of sulphuric acid.
C. The Haber process for the manufacture of ammonia.
D. The manufacture of margarine from unsaturated vegetable oils
7. The table shows the results of two tests carried out on separate portions of a solution of salt X.
test
observation
1 acidified aqueous barium nitrate
white precipitate
added
white precipitate soluble in an excess
2 aqueous sodium hydroxide
of aqueous sodium hydroxide
added
What is X?
A. calcium chloride
B. iron(II) sulphate
C. lead(II) nitrate
8. When 1 volume of gas X reacts with exactly 5 volumes of oxygen it forms
Water only. What is gas X?
A. methane, CH4
C. propane, C3H8
B. ethane, C2H6
D. butane, C4H10
D. zinc sulphate
carbon dioxide and
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9. The tables show the properties of four compounds.
Which compound could be ethanoic acid?
compound
degree of ionisation
addition of an aqueous solution of
in water
the compound to magnesium
A
high
hydrogen produced
B
high
no reaction
C
low
hydrogen produced
D
low
no reaction
10. Amino acids are produced when proteins are
A. hydrolysed.
B. oxidised.
C. polymerised.
D. substituted.
11. Which statement about the Periodic Table is correct?
A. the melting point of the elements increases down Group I
B. the reactivity of the elements increases down Group VII
C. the reactivity of the elements decreases down Group I
D. the colour of the elements becomes darker down Group VII
12. Sulfur dioxide and oxygen react together.
2SO2(g) + O2(g) 2SO3(g) ΔH
-197 kJ / mol-1
Which change(s) will increase both the rate of reaction and the equilibrium concentration of SO3?
1) adding a catalyst
2) increasing temperature
3) increasing pressure
A. 1 only
B. 2
C. 1 and 3
D. 3 only
13. Which element exists as a macromolecule?
A. carbon
B. hydrogen
C. oxygen
D. sodium
14. Which substance can conduct electricity by the movement of ions?
A. copper
C. mercury
B. graphite
D. sodium chloride
15. Sulfuric acid and potassium hydroxide can react together to form potassium
hydrogensulfate,
KHSO4, and water only.
Which amounts of the reactants are required?
A. equal masses of sulfuric acid and potassium hydroxide
B. equal numbers of moles of sulfuric acid and potassium hydroxide
C. 1 mol of sulfuric acid to 2 mol of potassium hydroxide
D. 2 mol of sulfuric acid to 1 mol of potassium hydroxide
16. Which substance does not react with hydrochloric acid?
A. zinc carbonate
B. zinc hydroxide
C. zinc metal
D. zinc nitrate
17. The table shows the energy released by the complete combustion of some compounds used as
fuels.
compound
formula
Mr
ΔH in kJ / mol
Benzene
C6H6
78
–3270
Heptanes
C7H16
100
–4800
Octane
C8H18
114
–5510
propane
C3H8
44
–2200
Which fuel releases the least energy when 1 g of the compound is completely burned?
A. benzene
B. heptane
C. octane
D. propane
18. Ammonia is made by a reversible reaction between nitrogen and hydrogen.
N2(g) + 3H2(g )
2NH3(g) ( ΔH = –92 kJ / mol)
What is the effect of increasing the pressure in this process?
A. Less heat is produced.
C. More nitrogen is present at equilibrium.
B. More ammonia is formed.
D. The reaction slows down.
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19 .Which change involves reduction?
A. calcium carbonate to calcium oxide
C. ethene to poly(ethene)
B. copper to brass
D. sand to silicon
20. Which process does not involve the use of a transition element?
A. the manufacture of margarine from vegetable oil
B. the manufacture of sulfuric acid in the Contact process
C. the purification of river water to produce drinking water
D. the removal of combustion pollutants from car exhaust gases
21. Element Q is in Period 3 of the Periodic Table. It can form ions with the formula Q 3–. Which element
is most likely to be Q?
A. aluminium
B. arsenic
C. phosphorus
D. sulfur
22. Which property would all the hydrogen compounds of the Group VII elements possess?
A. be covalent
C. form alkaline aqueous solutions
B. be solids at room temperature
D. conduct electricity when molten
23. In which solid can layers of atoms slide over each other?
A. diamond
B. graphite
C. haematite
D. silica
24 .Which ion causes the acidity in dilute hydrochloric acid?
A. Cl–
B. H+
C. H2
D. OH–
25. Which metal can react rapidly with steam but reacts only very slowly with cold water?
A. calcium
B. copper
C. iron
D. potassium
26.Which gas turns moist blue litmus paper red and produces a precipitate when bubbled through
calcium hydroxide solution?
A. CO
B. CO2
C. HCl
D. NH3
27. Which process is an example of cracking?
A. C2H4 + H2O → C2H5OH
C. C3H8 + 5O2 → 3CO2 + 4H2O
B. C3H6 + H2 → C3H8
D. C4H10 → C2H4 + C2H6
28. A hydride is a compound containing only two elements, one of which is hydrogen. Which element
can form the greatest number of different hydrides?
A. carbon
B. chlorine
C. nitrogen
D. oxygen
29. A liquid reacts with each of sodium carbonate, potassium hydroxide and ethanol. What is the liquid?
A. aqueous ammonia
C. ethyl ethanoate
B. ethanoic acid
D. sodium hydroxide
30.Compound X and compound Y combine to form a polymer.
HOOC
COOH
H2N
NH2
Compound X
compound Y
Which of the statements about the polymer and its formation is not correct?
A. Ammonia is formed during the production of the polymer
B. Hydrolysis of the polymer produces X and Y
C. The polymer is a polyamide.
D. The polymer is formed by a condensation reaction.
31. Which statement is not correct?
A. Air is a mixture.
C. Methane is a compound.
B. Ammonia is a compound.
D. Sea water is a compound
32. A radioactive isotope of carbon has more nucleons than the non-radioactive isotope, 126C. How
many protons, neutrons and electrons could there be in this radioactive isotope of carbon?
protons
neutrons
electrons
A
6
6
6
B
6
8
6
C
8
6
8
D
8
8
8
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33. Which molecule has the largest number of electrons involved in covalent bonds?
A. C2H4
B.CO2
C. CH3OH
D. N2
34. An element, E, forms a hydride, E H4, which contains 90.0% by mass of E.
If the relative atomic mass of hydrogen is 1, what is the relative atomic mass of E?
A. 9
B. 36
C. 86
D. 90
35. A piece of chalk has a mass of 23.0g. Chalk is impure calcium carbonate. When analysed, the chalk is
found to contain 0.226 moles of pure calcium carbonate. [Mr : CaCO3 =100]
What is the percentage purity of the piece of chalk?
A. 0.983%
B. 1.02%
C. 77.0%
D. 98.3%
36. Which element is most likely to be used as an industrial catalyst?
A. Na
B. Ni
C. Pb
D. Sr
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36. Which solution containing one mole per dm of the compound would have the lowest pH?
A. ethanoic acid
C. sodium
D. sodium
B. hydrochloric
chloride
hydrogencarbona
acid
te
37. Which statement about oxides is correct?
A. A basic oxide is an oxide of a non-metal.
C. An amphoteric oxide contains a metal.
B. Acidic oxides contain ionic bonds.
D. Basic oxides are always gases.
38. Which statement about the properties of propane and hexane is correct?
A. Propane has a higher boiling point than hexane.
B. Propane has a higher relative molecular mass than hexane.
C. Propane has more isomers than hexane.
D. Propane is more flammable than hexane.
39. Which particle is found in iodine vapour?
A. I
B. I–
C. I+
D. I2
40. Which property would all the hydrogen compounds of the Group VII elements possess?
A. be covalent
C. form alkaline aqueous solutions
D. conduct electricity when molten
B. be solids at room temperature
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Part 2
Section A
Answer all the questions in this section in the spaces provided.
A1. Choose from the following elements to answer the questions below.
Argon
bromine
carbon
hydrogen
Iodine
iron
neon
sulphur
Each element can be use used once, more than once, or not at all.
Name an element which
(a) forms a basic oxide,
.....................................................................................................................................
(b)
is a liquid at room temperature and pressure,
............................................................................................................................. ..........
(c)
reacts with aqueous copper(II) sulphate to give a pink solid,
.......................................................................................................................................
(d)
is formed during the electrolysis of concentrated aqueous sodium chloride,
.......................................................................................................................................
(e)
has a giant molecular structure.
.......................................................................................................................................
A2. Ethanol, CH3CH2OH, is a liquid fuel. Ethanol can be manufactured either from glucose,
C6H12O6, or from ethene.
(a) Briefly describe the manufacture of ethanol from glucose.
Include the balanced equation in your answer.
.........................................................................................................................................
.........................................................................................................................................
............................................................................................................................. ............
......................................................................................................................................
(b) (i) Draw the displayed formula for ethene.
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(ii) Name the substance that reacts with ethene to make ethanol.
............................................................................................................................. ......
(iii) Give the conditions needed for this reaction.
...................................................................................................................................
……………………………………………………………………………………………………………………………..
A3. Petroleum is a complex mixture of hydrocarbons. Petroleum is a source of many useful
fuels.
(a) What is meant by the term hydrocarbon?
............................................................................................................................. ............
.........................................................................................................................................
(b) Petroleum is separated by fractional distillation.
(i) Complete the following table about the fractions obtained from petroleum.
Fraction
petrol (gasoline)
paraffin (kerosene)
diesel
bitumen
Use
fuel for cars
fuel for diesel engines
(ii) Name one other fraction obtained from petroleum.
..................................................................................................................... .........
(c) Fractional distillation of petroleum does not produce sufficient of some fractions to match
demand.
Cracking is used to convert large hydrocarbon molecules into smaller molecules that
Are more in demand?
A hydrocarbon of molecular formula C12H26 is cracked.
(i)
Suggest the formula of one alkane that may be produced.
..................................................................................................................................
(ii)
Suggest the formula of one alkene that may be produced.
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.................................................................................................................................
(iii)
Describe a chemical test that can be used to distinguish between an alkene and an
alkane.
chemical test .............................................................................................................
result with alkane ......................................................................................................
result with alkene ......................................................................................................
Section B
B1. Methane, CH4, is used as a fuel. The complete combustion of methane can be represented
by the equation below.
H
H
C
H +
2O
O
O
C
O+
H
2O
H
H
ΔH = –890 kJ/mol
(a) Explain why this reaction is exothermic in terms of the energy changes that take place during
bond breaking and bond making.
(b) Calculate the energy released when 4.0 g of methane is completely combusted.
(c) Draw the energy profile diagram for the complete combustion of methane.
Label on the diagram the activation energy and the enthalpy change.
(d) Draw a ‘dot and cross’ diagram to show the bonding in methane.
You only need to draw the outer (valence) ele ctrons of carbon
B2. The table gives information about the first five members of the homologous series of
carboxylic acids
name of acid
formula
relative
molecular mass
melting point / °C
boiling point / °C
methanoic acid
HCO2H
46
8.4
101
ethanoic acid
CH3CO2H
60
17
118
propanoic acid
C2H5CO2H
74
-22
141
butanoic acid
C3H7CO2H
88
-8
164
pentanoic acid
(a) (i) Predict the formula and the relative molecular mass for pentanoic acid.
(ii) Explain why it is easier to predict the boiling point of pentanoic acid than the melting point.
(b) Draw the displayed formula for propanoic acid.
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(c) Analysis of an organic acid isolated from red ants shows that it contains 0.060 g of carbon,
0.010g of hydrogen and 0.16 g of oxygen.
Calculate the empirical formula for this acid.
(d) Ethanoic acid reacts with magnesium oxide.
Name the products formed and write a balanced equation for the reaction.
(e) Describe how ethanoic acid can be converted into ethyl ethanoate.
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