Chemistry Past Questions

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Past Questions

2,505 questions
Question 1 of 20 2,505 total questions
Question 71
jamb 2024

Hydrogen chloride gas and ammonia can be used to demonstrate the fountain experiment because they are

Alight
Bvolatile
Cvery soluble in water
Dheavy gases
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Question 72
jamb 2024

A radioactive element of mass 1g has half-life of 2 minutes, what fraction of the substance would have disintegrated after 10 minutes?

A1/4
B1/8
C1/16
D1/32
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Question 73
jamb 2024

Hydrochloric acid is not suitable in the preparation of ethanoic acid because it

Ais too acidic
Bis too volatile
Ccan attack cork and rubber used as containers
Dturns blue litmus red
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Question 74
jamb 2024

After breathing in a test tube that contains acidified K\(_2\)Cr\(_2\)O\(_7\), a man noticed the change in the colour of K\(_2\)Cr\(_2\)O\(_7\) from orange to green. This suggests the presence of

Aalkanone
Balkanal
Calkanol
Dalkanoic acid
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Question 75
jamb 2024

What accounts for the low melting and boiling points of covalent molecules?

AThey have weak intermolecular forces.
BThey are three-dimensional structures.
CThey have definite shapes.
DThey possess shared electron pairs
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Question 76
jamb 2024

The general molecular formula C\(_n\)H\(_{2n-2}\) represents that of an

Aalkyne
Balkene
Calkane
Dalkanal
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Question 77
jamb 2024

Benzene formed nitrobenzene at temperature of 60\(^0\)C when it reacts with mixture of concentrated trioxonitrate(V) acid and concentrated 

Aphosphoric acid
Bhydrochloric acid
Ctetraoxosulphate(VI) acid
Dhydrogen iodide
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Question 78
jamb 2024

Alkylation of benzene is catalyzed by 

Apalladium
Bnickel
Csunlight
Daluminium chloride
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Question 79
jamb 2024

C\(_x\)H\(_y\)O + 5O\(_2\)  →  4CO\(_2\)  +  4H\(_2\)O

C\(_x\)H\(_y\)O in the equation is

ACH\(_2\)O
BC\(_2\)H\(_6\)O
CCH\(_4\)O
DC\(_2\)H\(_4\)O
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Question 80
jamb 2024

The reaction between alkanoic acids and alkanols in the presence of an acid catalyst is known as

Asaponification
Bdehydration
Cesterification
Dhydrolysis
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Question 81
jamb 2024

The amount of Faraday required to discharge 4.5 moles of Al\(^{3+}\) is

A13.5
B4.5
C7.5
D1.5
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Question 82
jamb 2024

An organic compound with general formula RCOR' is an

Aalkanone
Balkanal
Calkanoate
Dalkanoic acid
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Question 83
jamb 2024

The hybridization scheme in ethyne is

Asp
Bsp\(^3\)
Csp\(^2\)d
Dsp\(^2\)s
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Question 84
jamb 2024

C\(_2\)H\(_{4(g)}\)  +  3O\(_{2(g)}\) → 2CO\(_{2(g)}\)  +  2H\(_2\)O\(_{(g)}\)

The above equation represents the combustion of ethene.If 10cm\(^3\) of ethene is burnt in 50cm\(^3\) of oxygen, what would be the volume of oxygen that would remain at the end of the reaction?

A20cm\(^3\)
B40cm\(^3\)
C60cm\(^3\)
D50cm\(^3\)
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Question 85
jamb 2024

In a chemical reaction, surface area of reactants can affect

ACaCO\(_3\) + 2HCl → CaCl\(_2\) + H\(_2\)O + CO\(_2\)
BMgCl\(_2\) + H\(_2\)SO\(_4\) → MgSO\(_4\) + 2HCl
CH\(_2\) + Cl\(_2\) → 2HCl
DNaOH + HCl → NaCl + H\(_2\)O
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Question 86
jamb 2024

An oxide of nitrogen that can rekindle a glowing splint is 

Anitrogen(I)oxide
Bnitrogen(II)oxide
Cnitrogen(IV)oxide
Ddinitrogen tetraoxide
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Question 87
jamb 2024

Which of the following represents an order of increasing reactivity?

AAu < Cu < Sn < Fe < Ca
BCa < Fe < Sn < Cu < Au
CAu < Cu < Fe < Sn < Ca
DCa < Sn < Fe < Cu < Au
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Question 88
jamb 2024

The main constituent of water-glass is

Acalcium trioxosilicate(IV)
Bcalcium trioxosulphate(IV)
Csodium trioxosulphate(IV)
Dsodium trioxosilicate(IV)
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Question 89
jamb 2024

The term strong and weak acids is used to indicate the 

Anumber of H\(^+\) released by an acid
Bnumber of OH\(^-\) released by an acid
Cextent of ionization of an acid
Dstrength of its action on substance
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Question 90
jamb 2024

The reaction of hydrogen and chlorine to produce hydrogen chloride gas is explosive in 

Adiffused light
Bsunlight
Cinfrared light
DRaman light
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