Chemistry Past Questions

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2,505 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10
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Past Questions

2,505 questions
Question 1 of 20 2,505 total questions
Question 41
jamb 2025

In the laboratory preparation of Chlorine, the gas is passed through a wash bottle of water to 

Adilute it
Babsorb HCl gas
Cneutralize it
Dabsorb the Cl\(_2\) gas
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Question 42
jamb 2025

The major product when 2-methylpropene reacts with HCl is

A2-chloro, 2-methylpropane
B1-chloro,2-methylpropane
C3-chloro, 2-methylpropane
D2-chloro,3-methylbutane
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Question 43
jamb 2025

Alkenes are represented with the general molecular formula 

AC\(_n\)H\(_{2n}\)
BC\(_n\)H\(_{2n-2}\)
CC\(_n\)H\(_{2n+2}\)
DC\(_n\)H\(_{2n+1}\)OH
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Question 44
jamb 2025

What is the molecular mass of an alkanoic acid, if 0.5 mole of the acid weighs 44g?

A72
B88
C60
D46
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Question 45
jamb 2025

Iron produced directly from a blast furnace is

Awrought iron
Bcast iron
Cpig iron
Dcarbon steel
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Question 46
jamb 2025

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

AThey have weak intermolecular forces
BThey have definite shapes
CThey are three dimensional structures
DThey possess shared electron pairs
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Question 47
jamb 2025

Acid radicals are present in 

ACO\(_3\)\(^{2-}\), PO\(_4\)\(^{3-}\), Mg\(^{2+}\)
BCO\(_3\)\(^{2-}\), SO\(_4\)\(^{2-}\), Na\(^+\)
CCO\(_3\)\(^{2-}\), SO\(_4\)\(^{2-}\), NO\(_3\)\(^-\)
DCO\(_3\)\(^{2-}\), SO\(_4\)\(^{2-}\), K\(^+\)
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Question 48
jamb 2025

The following is not a water pollutant?

Awarm water affluent
Binorganic fertilizers
Coxygen gas
Dbiodegradable waste
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Question 49
jamb 2025

Which of the following pairs of elements will exhibit diagonal relationship?

ABe and Si
BNa and Be
CLi and Al
DB and Si
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Question 50
jamb 2025

The time required to deposit 4.5g of copper from CuSO\(_4\) solution by passing a current of 2.5 Amperes is (Cu = 64g ; 1F = 96500C/mol)

A2714 sec
B2527 sec
C5428 sec
D6785 sec
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Question 51
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 52
jamb 2025

Water drops are spherical in shape because of 

Apolarity
Bviscocity
Cdensity
Dsurface tension
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Question 53
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
View Explanation & Discuss
Question 54
jamb 2025

2X + 2HCl  → 2XCl  +  H\(_2\)

In the equation above, X is 

AK
BMg
CCa
DBa
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Question 55
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 56
jamb 2025

The sublimation of solid to gas involves

Aenergy absorption
Bvapourization
Cmelting
Dosmotic diffusion
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Question 57
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 58
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 59
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 60
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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