Chemistry Past Questions

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Past Questions

2,505 questions
Question 1 of 20 2,505 total questions
Question 631
jamb 2005

What is the correct IUPAC name for NO\(_{2} ^{-}\)?

ADioxonitrate (IV) ion
BTrioxonitrate (III) ion
CTrioxonitrate (IV) ion
DDioxonitrate (III) ion
View Explanation & Discuss
Question 632
jamb 2005

When sulphur (IV) oxide is passed into a solution of sodium hydroxide for a long time, it eventually produces a solution of

ANaHSO4
BNa2SO3
CNaHSO3
DNa2SO4
View Explanation & Discuss
Question 633
jamb 2005

A concentrated solution containing H\(^+\), Cu\(^{2+}\), OH\(^-\) and Cl\(^-\) was electrolyzed using platinum electrodes.
The ion that will be discharged at the cathode is?

ACu2+
BCl-
CH+
DOH-
View Explanation & Discuss
Question 634
jamb 2005

2H\(_2\) + O\(_2\) → 2H\(_2\)O    ΔH = - 571kJ
In the equation above, how much heat will be liberated if 12.0g of hydrogen is burnt in excess oxygen?

A-1142 kJ
B-571 kJ
C+1142 kJ
D-1713 kJ
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Question 635
jamb 2005

In which of the following reactions can the oxidation number of the nitrogen be said to have increased?

A2NO(g) + O2(g) → 2NO2(g)
B2NO(g) + Cl2(g) → 2NOCl(l)
CFeSO4(aq) + NO(g) → Fe(NO)SO4(s)
DNO(g) + Br2(l) → 2NOBr(l)
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Question 636
jamb 2005

When iron is exposed to moisture and it rusts, the value of ΔG for the reaction is

Aneutral
Bzero
Cpositive
Dnegative
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Question 637
jamb 2005

Phenolphthalein in acidic solution is

Ared
Borange
Ccolourless
Dyellow
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Question 638
jamb 2005

Which of the following ions require the largest quantity of electricity for discharge at an electrode?

A4.0 moles of Cl-
B3.0 moles of Na+
C2.5 moles of Cu2+
D2.0 moles of Al3+
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Question 639
jamb 2005

Which of the following equimolar solutions will have the highest pH?

ACH3COOH
BNaOH
CHCl
DNH4OH
View Explanation & Discuss
Question 640
jamb 2004

The IUPAC nomenclature of the compound above is

A2-ethylpentane
B3,4-dimethylhexane
C2,3-dimethylhexane
D2-ethylhexane
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Question 641
jamb 2004

In the experiment above, X is a mixture of nitrogen, carbon (IV) oxide and

Awater
Bimpurities
Cinert gas
Doxygen
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Question 642
jamb 2004

In the production of soap, concentrated sodium chloride solution is added to

AIncrease the solubility of soap
BDecrease the solubility of the soap
CSaponify the soap
DEmulsify the soap
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Question 643
jamb 2004

Alkanol + Alkanoic acid  ⇌  Ester + Water
The reverse reaction above is known as

AHydrolysis
BSaponification
CHydration
DFermentation
View Explanation & Discuss
Question 644
jamb 2004

C\(_2\)H\(_5\)OH(aq) → Y
If the above reaction takes place in conc. H\(_2\)SO\(_4\) at 180\(^0\)C, Y represents

ACH4
BC2H5COOH
CC2H4
DCH3OCH3
View Explanation & Discuss
Question 645
jamb 2004

CH\(_3\)COOH(g) → CH\(_4\)(g) + CO\(_2\)(g)
The reaction above is

ACarboxylation
BDecarboxylation
CAcidification
DEsterification
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Question 646
jamb 2004

Vulcanization involves the removal of

Aa monomer
Bthe single bond
Cthe double bond
Da polymer
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Question 647
jamb 2004

Which of these reagents can confirm the presence of a triple bond?

ABromine water
BAcidified KMnO4
CCopper (I) chloride
DBromine gas
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Question 648
jamb 2004

A characteristic of the alkane family is

AAddition reaction
BElimination reaction
CSubstitution reaction
DNeutralization reaction
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Question 649
jamb 2004

An isomer of C\(_5\)H\(_{12}\) is

AButane
B2 – methylbutane
C2 – methylpropane
D2 – ethylbutane
View Explanation & Discuss
Question 650
jamb 2004

The alkyl group can be represented by the general formula

ACnH2n+1
BCnH2n
CCnH2n+2
DCnH2n-2
View Explanation & Discuss
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