Chemistry Past Questions

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92 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10
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Past Questions

92 questions
Question 1 of 20 92 total questions
Question 31
jamb 2004

When steam is passed over red-hot carbon, the substances produced are

AHydrogen and trioxocarbonate (IV) acid
BHydrogen, oxygen and carbon (IV) oxide
CHydrogen and carbon (II) oxide
DHydrogen and carbon (IV) oxide
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Question 32
jamb 2004

Which of the following gases can be collected by the method of downward delivery?

AChlorine
BOxygen
CAmmonia
DHydrogen
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Question 33
jamb 2004

The allotrope of carbon used in the decolourization of sugar is

AGraphite
BSoot
CCharcoal
DLampblack
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Question 34
jamb 2004

Which of the following shows little or no net reaction when the volume of the system is decreased?

AH2(g) + I2(g) ↔ 2HI(g)
B2NO2(g) ↔ N2O4(g)
CPCl5(g) ↔ PCl3(g) + Cl2(g)
D2O3(g) ↔ 3O2(g)
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Question 35
jamb 2004

N\(_2\)O\(_4\),(g) ↔ 2NO\(_2\)(g)
In the endothermic reaction above, more product formation will be favoured by

Aa constant volume
Ban increase in pressure
Ca decrease in pressure
Da decrease in volume
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Question 36
jamb 2004

Which of the following hydrogen halides has the highest entropy value?

AHF
BHCl
CHBr
DHI
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Question 37
jamb 2004

2CO(g) + O\(_2\)(g) → 2CO\(_2\)(g)
Given that ΔH[CO]is -110.4 kJmol-1 and ΔH[CO\(_2\)] is -393.0 kJmol-1, the energy change for the reaction above is

A-503.7 kJ
B-282.6 kJ
C+282.6 kJ
D+503.7 kJ
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Question 38
jamb 2004

The mass of silver deposited when a current of 10A is passed through a solution of silver salt for 4830s is
[Ag = 108, 1F = 96500 Cmol-1]

A108.0g
B54.0g
C27.0g
D13.5g
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Question 39
jamb 2004

In the electrolysis of brine, the anode is

Aplatinum
Bcopper
Czinc
Dcarbon
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Question 40
jamb 2004

Which of the following acts as both reducing and oxidizing agent?

AH2
BSO2
CH2S
DCO2
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Question 41
jamb 2004

ZnO(s) + CO(g) → Zn(s) + CO\(_2\)(g)
In the reaction above, Zinc has been

Adecomposed
Bdisplaced
Coxidized
Dreduced
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Question 42
jamb 2004

The oxidation state of chlorine in HClO\(_4\) is

A-5
B-1
C+1
D+7
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Question 43
jamb 2004

What volume of 0.5 mol dm\(^{-3}\) H\(_2\)SO\(_4\) will exactly neutralize 20cm\(^3\) of 0.1 mol dm\(^{-3}\) NaOH solution?

A2.0 cm3
B5.0 cm3
C6.8 cm3
D8.3 cm3
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Question 44
jamb 2004

Which of the following compound is a normal salt?

ANaHS
BNaHSO4
CNaHCO3
DNa2CO3
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Question 45
jamb 2004

Calcium tetraoxosulphate (VI) dissolves in water only sparingly to form a

Asolution
Bsuspension
Cprecipitate
Dcolloid
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Question 46
jamb 2004

The solubility in moldm\(^{-3}\) of 20g of CuSO\(_4\) dissolved in 100g of water at 180\(^o\)C is
[Cu = 64, S = 32, O =16]

A0.13
B0.25
C1.25
D2.00
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Question 47
jamb 2004

A carcinogenic substance is

Aasbestos dust
Bsawdust
Cnitrogen (II) oxide
Dcarbon (II) oxide
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Question 48
jamb 2004

Pollution of underground water by metal ions is very likely in the soil that has high

Aacidity
Balkalinity
Cchloride content
Dnitrate content
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Question 49
jamb 2004

Hardness of water is caused by the presence of ions of

Amagnesium and silver
Bcalcium and magnesium
Csodium and potassium
Dcalcium and sodium
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Question 50
jamb 2004

Which of the following mixture of gases is likely to burn in flame?

Aneon and hydrogen
Bnitrogen and helium
Chelium and neon
Dneon and nitrogen
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