UME 1980 CHEMISTRY QUESTIONS
1. In
an attempt to remove sugar from a breaker containing a quantity of sand and
sugar, 2M ammonium chloride solution was accidentally added instead of water.
Which of the following methods could be used to remove the ammonium chloride
from the mixture? A. fractional distillation, B. crystallization, C. filtration
followed by sublimation, D. Evaporation followed by sublimation E. filteration
followed by sublimation.
2. The
alloy duralumin is used for the building of aeroplane because it A. absorbs
heat readily from the sun thereby preventing the inside of the plane from
getting too cold at high altitudes. B. reflects sunlight readily, thereby
keeping the inside of the plane cool, C. is extremely durable and possesses
reflective ability, D. is easily the lightest building material, E. possesses
both strength and lightness.
3. A
solution X, on mixing with AgNO3 solution, gives a white precipitate
soluble in NH3 A solution Y contains. A. Ag+ B. Pb2+
C. Pb4+ D. Zn2+ E.
Al3+
4. 10cm3
of CO is mixed and sparked with 100cm3 of air containing 21%O2.
If all the volumes are measured at S.T.P, the volume of resulting gases would
be? A. 90cm3 B. 100cm3, C. 105cm3, D. 110cm3,
E. 115cm3
5. A
sample of an oxide of mercury weighed 1.00g. when this was heated, oxygen was
given off, and 1.00g of mercury metal only was left. What is the formula of the
oxide? A. Hg2O, B. HgO2 C. HgO4 D. HgO, E.
none of the above. (Hg = 200, 0 = 16)
6. On
heating, under suitable conditions, 1 litres of a monatomic gas, X, combines
with 11/2 litres of oxygen from an oxide. What is the formula of the oxide? A.
XO3 B. X2O3, C. X3O2, XO2
E. none of the above
7. If 1
litre of 2.2M sulphuric acid is poured into a bucket containing 10 litres of
water, and the resulting solution mixed thoroughly, the resulting sulphuric acid
concentration will be. A.2.2M, B. 1.1M, C. 0.22M, D. 0.11M E. 0.20M
8. 1.0g
of CaCO3 was treated with excess 0.1M HCI. At the end of the
reaction, the acid still left unreached required 25cm3 of 0.1M Na2CO3
to neutralize it. What was the original volume of the acid? (Na = 23, Ca = 40,
C = 12, O = 16 CI = 35.5). A. 220cm3,
B. 230cm3, C. 240cm3, D. 250cm3 E. 260cm3
9. Which
of the following reaction is correct as written? A. FeCI2 + 3NH4OH
Fe(OH)3 + 3NH4CI, B. Pb2O2
+ 4HCI
PbCI2 + 2H2O, C. PbNO3
+ H2SO4
PbS + 2HNO3, D. NaOH + H2SO4
NaHSO4 + H2O, E. 2NH4NO3
N2 + 2H2O
10. How
many grams of hydrogen gas will be liberated when 6g of magnesium ribbon
dissolves in 500cm3 of 6M HCI? (Mg = 24, H = 1, CI = 35.50). A.
1.2g, B. 0.7g, C. 0.5g, D. 0.3g, E. 0.12g
11. Under
high pressure, real gases do not obey gas laws because their molecules A. have
become more energetic, B. have become less energetic, C. have become smaller in
size, D. decompose into atoms, E. start repelling each other.
12. 500cm3
of oxygen was collected over water at 30oC and 752 mmHg pressure.
What is the volume of dry oxygen at S.T.P? (Vapour pressure of water at 30oC =
32 mmHg) A. 475cm3 B. 415cm3 C. 586cm3 D. 500cm3,
E. 427cm3
13. Which
of the following statements is an exception in the assumption of the kinetic
theory of gases? A. gases are composed of many elastic particles, B. the
particles are of negligible size, C. the particles are in constant random
motion, D. the particles are of negligible mass, E. the particles collide with
each other.
14. Which
of the following statements is true? A. metals conduct electricity while
non-metals do not. B. metals have high density, C. metals form basic oxides,
non-metals form acidic oxides, D. in the electro-chemical series, metals are
above hydrogen, E. metals lose electrons while non-metals gain electrons during
normal reactions
15. 5.00g
of a hydrated salt of barium when heated to a constant weight gave 4.26g of
anhydrous salt with molecular weight of 208. The number of molecules of water
of crystallization in the hydrated salt is A. 10, B. 7 C. 5, D. 2, E. 1
16.
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Alkaline
pyrogallol
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CaCl2
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Air
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17. Chlorine,
bromine and iodine resemble each other in that all A. dissolve in alkalis, B.
react violently with hydrogen without heating, C. displace each other from
solutions of their salts, D. are gases E. are liquids.
18. The
following is an arrangement of elements in order of deceasing number of outer
electrons; one of the elements is strongly placed. Which is it? ALUMINUM, CHLORINE, SILICON, MAGNESIUM,
SODIUM, A. Chlorine, B. Aluminum, C. Silicon, D. magnesium, E. Sodium
19. Element
X has a total of 19 electrons and can react with oxygen to form an oxide. Which
of the following statements is NOT true of the oxide of the element? A. when
exposed to air, it slowly changes to liquid, B. its solution in water conducts
electricity, C. its solution in water, on evaporation, gives a white solid, D.
its solution in water liberates hydrogen when in contact with aluminum metal.
E. its oxide, when strongly heated, regenerates the elements X.
20. Which
ONE of the following statements is true? A. all alkali metal salts dissolves
with dissociation in water, B. most ionic substances are easily vaporized, C.
ionic substances exist only as liquids, D. non-ionic substances are good
electrolytes, E. Nitrogen exists in a trivalent state in ammonium salts.
21. When
ethane gas react with chlorine gas to form 1,2-dichloroethane, the reaction is
called A. substitution, B. addition, C. Polymerization D. hydrolysis, E.
reduction
22. 20cm3
of 1 MH2SO4 is mixed with 20cm3 of 1M NaoH.
The resulting solution is A. acidic with a molarity of 0.25M H2SO4,
B. acidic with a molarity of 0.25M H2SO4, C. neutral, D.
alkaline with a molarity of 0.25M NaOH, E. alkaline with a molarity of 0.50M
NaOH
23. Which
of the following is acceptable as the organic product of the reaction of
ethanic acid and ethanol with an acid catalyst? A. Ethyl ethanoate, B.
Methyl ethanoate, C. Ethyl Methyl
ketone, D. Butanol, E. None
24. In
the above experiment X is A. pure nitrogen, B. a mixture of nitrogen and carbon
dioxide, C. a mixture of nitrogen and carbon dioxide, D. a mixture of oxygen
inert gases, E. a mixture of nitrogen and inert gases.
25. Given
the mean atomic mass of chlorine prepare in the laboratory to be 35.5 and
assuming that chlorine contains two isotopes of mass number 35 and 37, what
is the percentage composition of the
isotope of mass number 35? A. 20, B. 25, C. 50, D. 75, E. 90
26. When
dilute hydrochloric acid is added to iron(II)sulphide, the gas evolved will A.
turn moist red litmus paper blue, B. turn lime water milky, C. blacken lead
acetate paper , D. rekindle a glowing
splint, E. burn with a squeaky pop.
27. In
which of the following is the oxidation state of oxygen different from its
value in water? A. OH, B. H2O+, C. O-, D. H2O2,
E. SO2
28. Which
of the following silver halides is readily soluble in ammonium hydroxide? A.
Agl, B. AgBr, C. AgCl, D. AgF, E. None of the above
29. The
chemical reaction which takes place at the anode (positive electrode) in
electrolysis is A. oxidation, B. Hydrolysis, C. dissociation, D. reduction, E.
disproportionation
30. Which
of the following does NOT happen when zinc rod is introduced into a solution of
copper (II) sulphate? A. electrons flow towards the zinc rod, B. the zinc rod
dissolves, C. the temperature of the solution changes, D. the blue colour of
the solution gradually disappears, E. copper metal is deposited
31. Hardening
of an oil may be achieved by A. boiling the oil with water, B. boiling the oil
with a catalyst, C. treating the oil with sodium hydroxide, D. treating the oil
with hydrogen and catalyst, E. distilling the oil with hydrogen and catalyst
32. A
cold aqueous solution of sodium chloride is electrolyzed using a graphite anode
and an iron cathode. In the course of the electrolysis, the electrolyte is
continuously stirred. The liquid left after electrolysis will therefore consist
of A. sodium hydroxide solution, B. chlorine water, C. pure water, sodium
hypochlorite solution, E. hydrochloric acid solution.
33. When
copper (II) sulphate solution is treated with excess ammonium hydroxide, a
precipitate is first formed and then this dissolves to give a deep the
solution. This deep blue solution is A. Cu(OH)2, B. CuSO45H2O,
C. (NH4)2SO4, D. Cu(NH3)4(OH)2,
E. CuSO4.(NH4)2SO4.2H2O.
34. The
IUPAC name for the compound below is
|
CH3 –
CH2 – C = C – CH3
H3C CH3
|
A.
2,3-dimethylpent-2,3-ene, B. 2,3- dimethylpent-2-ene, C.
3,4-dimethylpent-3-ene, D. 3,4-dimethylpentene, E. 3,4-dimethylhept-2-ene
35. Which
of the following tests would confirm unequivocally that a solution X contains
the sulphate ion if it gives with, A. silver nitrate solution, a white
precipitate insoluble in dilute HNO3, B. barium chloride solution, a
white precipitated insoluble in dilute H2SO4, C. barium
chloride solution, a white precipitated soluble in dilute HCl, D. barium
chloride solution, a white precipitate insoluble in dilute ammonia, E. barium
chloride solution, a white precipitate insoluble in dilute HCl.
36. When
chloride gas is passed into a solution of sulphur dioxide A. sulphur dioxide is
reduced to sulphur, B. the chlorine is oxidized to hydrochloric acid, C. dilute
sulphuric acid, D. hydrochloric acid and sulphur are produced, E. sulphur
trioxide is the only product.
37. Which
of the following compounds will take up two molecules of bromine?
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HO O
C = O C – C
C
- H
C = O H
HO
I II
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O
CH2 = CH
- C
H
III
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A.
I, B. II, C. III, D. I and II, E. I and III
38. A mixture
of ethanol, sodium dichromate, and water is allowed to drop gradually into a boiling
solution containing one part concentrated H2SO4 and three part of water and the
liberated gas is collected by cooling it with ice water to give a liquid. This
liquid is A. ethanoic acid, B. acetaldehyde, C. ethyl acetate, D. methanol, E.
ethylene
39. Which
of the following statements is false? A. acids react with carbonates,
liberating hydrogen, B. acids react with carbonates, liberating carbon dioxide,
C. acids conduct electricity and are decomposed by the current, liberating
hydrogen at the anode, D. acids have a sour taste, E. acids change the colour
of indicators.
40. The
best way of collecting chlorine is A. by downward displacement of air, B. by
upward displacement of air, C. over water, D. under water, E. over mercury
41. Cellulose
and starches can be classified as one of the following A. sugar, B. sucrose, C.
hydrocarbons, D. carbohydrates, E. isomers
42. If
one of the following oxides is heated with hydrogen of carbon using a Bunsen
burner, it is not reduced to the metal. Which one is it? A. lead oxide, B.
magnesium oxide, C. copper oxide, D. tin oxide, E. iron oxide.
43. Which
of the following is the correct order in increasing boiling points, of the
isomeric C5H12 compound?
|
C C
A. C-C-C-C-C<C-C-C-C<C-C-C
C
C C
B. C-C-C-C-C<C-C-C<C-C-C-C
C
C C
C. C-C-C<C-C-C-C-C<C-C-C-C
C
C C
D. C-C-C<C-C-C-C<C-C-C-C-C
C
C C
E. C-C-C-C<C-C-C<C-C-C-C-C
C
|
44. Which
of the following derivatives of nitrogen affords an aqueous solution having a
pH of less than 7? A. N2O, B. NO, C. NO2, D. NaNO3,
E. NH3
45. Detergent
are more advantageous than soaps in hard water districts because A. on
treatment with hard water, they either form soluble calcium ions, B. on
treatment with hard water, they form insoluble calcium salts, C. on treatment
with hard water, they form soluble sodium soaps, D. on treatment with hard
water, they are converted into soaps, E. on treatment with hard water, they
form more lather than soap does.
46. Which
of the following classes of organic compounds undergoes rapid oxidation with
bromine water? A. Alcohols, B. Alkenes, C. Carboxylic acids, D. Esters, E.
Alkanes
47.
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Mass
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2
(small pieces
of marble)
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1
(large pieces
of marble)
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Time
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A.
the initial slope of the curve is steepest and this occurs when small pieces of
marble are used and is due to a small surface area of reactant, B. the initial
slope of the curve is least steep and this occurs when large pieces of marble
are used and is due to a small surface area of reactant. C. the initial slope
of the curve is steepest and this occurs when small pieces of marble are used
and is due to a small surface area of reactant, D. the initial slope of the
curve is steepest and this occurs when large pieces of marble are used and is
due to the increased surface area of the reactant, E. the initial slope of the
curve is least steep and this occurs when small pieces of marble are used and
is due to the increased surface area of the reactant.
48. An
endothermic reaction is one during which heat is…and can be represented by the
symbol…. Which of the following combinations can be used accurately to complete
the above definition? A. liberated, - ∆H
B. Liberated, +∆H C. Absorbed, - ∆H,
D. Absorbed, +∆H, E. Absorbed, +∆G
49. The
synthesis of sulphuric acid by the contact process employs the following equilibrium
step as one of its stages: 2SO2(g) + O2(g)
2SO3(g) - ∆H
Which of the following conditions promotes the backward
reaction? A. increased pressure and decreased temperature, B. increased
pressure, increase temperature and the presence of a catalyst, C. decreased
pressure, increase temperature, D. decreased pressure, increased concentration
of oxygen and increased temperature, E. decreased pressure, decreased
concentration of oxygen and decreased temperature.
50.
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Bulb
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-
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+
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Battery
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Copper
electrodes
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Copper
Sulphate
solution
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A .
the bulb lights and copper is deposited at both electrodes, B. the bulb lights
and copper is deposited at the anode C. the bulb lights and copper deposited at the
cathode D. the bulb lights and copper is deposited at the cathode and
disappears from the anode E. the bulb lights ut no additional changes are
observed
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