Chemistry Past Questions

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Past Questions

4,306 questions
Question 1 of 20 4,306 total questions
Question 71
jamb 2025

In the electrolysis of brine using neutral electrode, which ion is discharged at the anode?

A2H\(^+\)
BNa\(^+\)
CCl\(^-\)
DOH\(^-\)
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Question 72
jamb 2025

Water drops are spherical in shape because of 

Apolarity
Bviscocity
Cdensity
Dsurface tension
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Question 73
jamb 2025

Alkanoic acids have higher boiling points than alkanols because

Aalkanoic acids are more volatile than alkanols
Balkanols are more polar than alkanoic acids
Calkanoic acids are larger molecules
Dalkanoic acids form stronger hydrogen bonds
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Question 74
jamb 2025

2X + 2HCl  → 2XCl  +  H\(_2\)

In the equation above, X is 

AK
BMg
CCa
DBa
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Question 75
jamb 2025

The products of the thermal decomposition of ammonium trioxonitrate(v) are

AN\(_2\)O and H\(_2\)O
BNO\(_2\) and H\(_2\)O
CN\(_2\)O and O\(_2\)
DNO\(_3\) and H\(_2\)O
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Question 76
jamb 2025

The sublimation of solid to gas involves

Aenergy absorption
Bvapourization
Cmelting
Dosmotic diffusion
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Question 77
jamb 2025

2Na  +  Cl\(_2\) → 2NaCl

In the reaction above, the specie that undergoes reduction is

ANa
BNaCl
CCl\(^-\)
DCl\(_2\)
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Question 78
jamb 2025

Nitrogen, a component of air is used for

Aproduction of cooling agent
Bproduction of margarine
Cproduction of HNO\(_3\)
Dmanufacturing of oil
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Question 79
jamb 2025

The compound CH\(_3\)CH(NH\(_2\))CH\(_2\)CH\(_2\)CH\(_3\) is an example of a

Aprimary amine
Btertiary amine
Cquaternary amine
Dsecondary amine
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Question 80
jamb 2025

NH\(_3\) \((_g\)) +  HCl\((_g\)) →   NH\(_4\)Cl \(_(g)\)

In the reaction above, increase in pressure will

Alower the equilibrium constant
Bfavour the product
Cfavour the reactant
Dincrease the equilibrium constant
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Question 81
jamb 2025

The acid used in making baking soda and soft drink is

Atartaric acid
Bfatty acid
Cboric acid
Dcitric acid
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Question 82
jamb 2025

Calculate the pH of 0.001M  KOH solution.

A11
B14
C12
D3
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Question 83
jamb 2025

When ΔH is positive and small, and ΔS is positive and large, the reaction will be

ANon-spontaneous
Bfavour forward reaction only
Cfavour backward reaction only
Dspontaneous
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Question 84
jamb 2025

The property of metal that makes it suitable as a catalyst is

Afilled f-orbital
Bpartially filled d-orbitals
Cpartially filled f-orbital
Dfilled d-orbital
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Question 85
jamb 2025

The dusty and sand particles present in the air is an example of 

Aa suspension
Ba dispersion
Can emulsion
Da saturated solution
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Question 86
jamb 2025

An example of an alkaline gas is

AHCl
BN\(_2\)
CNH\(_3\)
DNO\(_2\)
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Question 87
jamb 2025

In the table above, the two compounds that will combine in the presence of an acid-catalyzed compound, V is

AI and IV
BIII and IV
CI and II
DII and III
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Question 88
jamb 2025

The composition of petroleum varies because it is a 

Ahydrocarbon
Bliquid
Cmixture
Dnatural resource
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Question 89
jamb 2025

The molecule with the highest number of lone pair of electrons is 

AH\(_2\)O
BNH\(_3\)
CCH\(_4\)
DC0\(_2\)
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Question 90
waec 2024

Consider the reaction represented by the following equation: 

x Al  +  yCl\(_2\) → z AlCl\(_3\)

A2, 3 and 2
B2, 2 and 3
C1, 2 and 1
D1, 1 and 1
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