Chemistry Past Questions

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Past Questions

4,306 questions
Question 1 of 20 4,306 total questions
Question 2101
jamb 1980

Under high pressure, real gases do not obey gas laws because their molecules?

Ahave become more energetic
Bhave become less energetic
Chave become smaller in size
Ddecompose into atoms
Estart repelling each other
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Question 2102
jamb 1980
Which of the following reactions is correct as as written?
AFeCl2 + 3NH4OH → Fe(OH)3 + 3NH4Cl
BPb2O3 + 4HCl → PbCl2 + 2H2O
CPbNO3 + H2S → PbS + 2HNO3
DNaOH + H2SO4 → NaHSO4 +H2O
E2NH4NO3 → N2 + 2H2O
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Question 2103
jamb 1980

If 1 litre of 2.2M sulphuric acid is poured into a bucket containing 10 litre of water,and resulting solution mixed thoroughly, the resulting sulpuric acid concentration will be?

A2.2 M
B1.1 M
CO.22 M
D0. 11 M
E0.20 M
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Question 2104
jamb 1980

On heating, under suitable conditions, 1 litres of monoatomic gas,X, combines with 1½ litres of an oxide, What is the formula of the oxide?

AXO3
BX2O3
CX3O2
DXO2
ENone of the above
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Question 2105
jamb 1980

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?

AHg2O
BHgO2
CHgO2
DHgO
ENone of the above
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Question 2106
jamb 1980

10cm3 of CO is mixed and sparked with 100cm3 of air containing 21% O2. If all the volumes measured at S.T.P. the volume of resulting gases would be?

A90cm3
B100cm3
C105cm3
D110cm3
E115cm3
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Question 2107
jamb 1980
A solution X on mixing with AgNO3 solution, gives a white precipitate solution in NH3. A Solution Y, when added to X, also gives a white precipiate which is soluble on boiling. Solution Y contains?
AAg+ion
BPb2+ion
CPb4+ion
DZn2+ion
EAl3+ion
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Question 2108
jamb 1980
The alloy duralumin is used for the building of aeroplanes because it?
Aasborbs heat readily from sure thereby preventing the inside of the plane from getting cold at high attitudes
Breflects sunlight readily, thereby keeping the inside of the plane cool
Cis extremely durable and possesses reflective ability
Dis easily the lightest building material
Epossesses both strenght and lightness
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Question 2109
jamb 1980

In an attempt to remove sugar from a breaker containing a quantity of sand and sugar, 2 M ammonium chloride solution was accidentally added instead of water. Which of the following method could be used to remove the ammonium chloride from the mixture?

AFractional distillation
Bcrystallization
CFiltration followed by evaporation
DEvaporation followed by sublimation
EFiltration followed by sublimation
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Question 2110
jamb 1979

Which of the structural formula above is ethanoic acid is

AA
BB
CC
DD
EE
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Question 2111
jamb 1979

The IUPAC name for

A2-methylbut-3-ene
B2-methylbut-4-ene
C3-methylbut-2-ene
D3-methylbut-1-ene
E3-methylpent-1-ene
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Question 2112
jamb 1979

Consider the following exothermic reaction \(2SO_{2(g)} + O_{2(g)} = 2SO_{3(g)}\) . If the temperature of the reaction is reduced from 800ºC to 500ºC, and no other change takes place, then

Athe reaction rate increases
Bconcentration of SO3 decreases
Cconcentration of SO3 increases
DSO2 gas becomes unreactive
EO2 gas becomes unreactive
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Question 2113
jamb 1979

Pick out the correct statement

AZinc heated to redness reacts with steam to give oxygen and zinc oxide
BZinc heated to redness reacts with steam to give oxygen and hydrogen
CZinc does not react with hot or cold water
DZinc reacts with hot water to form zinc oxide and hydrogen
EZinc reacts very easily with cold water to give zinc oxide and hydrogen
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Question 2114
jamb 1979
A piece of metal (M) is dissolved in nitric acid and the resulting solution is treated with a small quantity of sodium hydroxide to produce a white precipitate (B) which redissolves on the addition of excess alkali. The precipitate (B)when ignited in a crucible produces the oxide of the metal(m). The METAL M is
AZn
BCu
CAl
DAu
ECa
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Question 2115
jamb 1979
Which of the following raw materials would be required from the smelting of iron ore in a blast furnace?
ACaCO 3
BZn(NO3)2
CCuSO4
DAICI3
ECaSO4
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Question 2116
jamb 1979
When excess ethanol is heated to 145 oC in the presence of concentrated sulphuric acid, the product is
Adiethyl ether
Bethyne
Cdiethyl sulphate
Dacetone
Eethanoic acid
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Question 2117
jamb 1979

A gas occupies a volume of 30.0 dm\(^3\) at S.T.P. What volume would it occupy at 91\(^0\)C and 380 mm Hg?

A20. 0dm3
B40.0dm3
C60. 0dm3
D80. 0dm3
E100. 0dm3
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Question 2118
jamb 1979
One of the following techniques can be used to show that chlorophyll pigment is a mixture of chemical compounds and not a single coloured compound
Acystallization
Bhydrolysis
Csublimation
Dfiltration
Echromatography
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Question 2119
jamb 1979

On heating anhydrous iron (ll) sulphate, in addition to producing iron (iii) oxide, which of the following is produced?

ASO2 (g) + FeS (s)
BSO3 (g) +FeS(s)
CSO2 (g) + SO3(g)
DSO2 (g) + H2S (g)
ESO3(g) + H2S(g)
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Question 2120
jamb 1979

Phosphorus burns in oxygen according to the equation P\(_4\) + 5 0\(_2\) → P\(_4\)O\(_{10}\). How many litres of oxygen will be required at S.T.P for complete oxidation of 12.4g of phosphorus? [P = 31,O = 16 and molar volume of a gas at S.T.P = 22.4 litres]

A5. 20
B11. 20
C2. 24
D20. 20
E6. 20
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