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Chemistry Past Questions

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45 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Past Questions

45 questions

Question 1 of 20 45 total questions

Question 1

waec 2014

The oxide from electric power station is

Acarbon (IV) oxide

Bcopper (ll) oxide

Cnitrogen (IV) oxide

Dsulphur (IV) oxide

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Question 2

waec 2014

The most common process in the extraction of metals from their ore is

Acatalysis

Belectrolysis

Coxidation

Dreduction

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Question 3

waec 2014

Which of the following gases is used to retard the vaporization of the filament in a light bulb?

AArgon

BHelium

CHydrogen

DOxygen

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Question 4

waec 2014

The purity of a solid sample can best be determined by its?

Aboiling point

Bmelting point

Cconductivity

Dsolubility

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Question 5

waec 2014

The production of biogas from the fermentation of waste materials is an example of

Acombustion

Bincineration

Crefining

Drecycling

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Question 6

waec 2014

Which of the following organic compounds could be represented by the empirical formula CH₂O?

AEthanal

BEthane

CEthanol

DEthanoic acid

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Question 7

waec 2014

Consider the reaction represented by the following equation: C₂H_4(g)
+ 30_2(g) → 2CO_2(g) + 2H₂O_(g)How many moles of ethene would be burnt to produce 0.1 mole of water?

A0.05 mole

B0.10 mole

C0.20 mole

D2.00 moles

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Question 8

waec 2014

The liquid hydrocarbon likely to be found in the fraction of crude oil used for domestic cooking is?

AC₃H₈

BC ₅H ₁₂

CC₁₃H₂₈

DC₂₀H₄₂

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Question 9

waec 2014

A colourless hydrocarbon with a sweet smell undergoes substitution reaction. The hydrocarbon is likely to be

Aalkanol

Bbenzene

Cester

Dmethane

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Question 10

waec 2014

The enzyme that catalyses the conversion of glucose te ethanol and carbon (IV) oxide is

Adiastase

Bmaltase

Cptyalin

Dzymase

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Question 11

waec 2014

The IUPAC name of the following organic compound is HOOC - COOH

Aethan - 1, 2 -dioc acid

Bethanoic acid

Coxalic acid

Dpropan - 1,2-dioic acid

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Question 12

waec 2014

Which type of reaction is illustrated by the following equation? C₁₂H₂₆ → 5C ₂H₄ + C ₂H₆

AAddition

BCracking

CHydrogenation

DPolymerization

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Question 13

waec 2014

Which of the following compounds determines the octane rating of petrol?

A1,2,3 - trimethyl pentane

B2,3,5 - trimethyl octane

C2,3,5 - trimethyl pentane

D2,2,4 - trimethyl pentane

View Explanation & Discuss

Question 14

waec 2014

Ethene molecules can be added to one another to form a long chain compound called a

Adimer

Bmonomer

Cpolymer

Dtrimer

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Question 15

waec 2014

Reduction is the process of

Aloss of electron

Bloss of hydrogen

Closs of oxygen

Daddition of electronegative elements

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Question 16

waec 2014

The reaction that occurs all the anode when CuSO_4(aq) is electrolyzed using carbon electrode is

A2H ^- _(aq) + 2e → H _2(g)

BCu²⁺ _(aq) + 2e → Cu _(s)

C4OH _(aq) _-4e → 2H₂O_(l) + O2 _(g)

DSO_4(aq)² _-2e → SO _2(g) + O_2(g)

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Question 17

waec 2014

Consider the reaction represented by the following equation: N_2(g) + 3H_2(g) ⇌ 2NH_{3(g)_{; ∆H^ϴ = -xkJ mol^-1. Which of the following conditions would increase the yield of NH₃?}}

AAddition of iron catalyst

BIncrease in the temperature of the system

CIncrease in the volume occupied by reactants

DIncrease in the total pressure of the system

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Question 18

waec 2014

Which of the following factors would affect the equilibrium constant?

AConcentration

BTemperature

CPressure

DVolume

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Question 19

waec 2014

Consider the reaction represented by the following equation: Na₂CO_3(aq) + 2HCl_(aq) \(\longrightarrow\) 2NaCl_(aq) + H₂O_(l) + CO_2(g) . What volume of 0.02 mol dm^-3 Na₂CO_3(aq) would be required to completely neutralize 40 cm³ of 0.10 mol dm^-3 HCl_(aq)?

A200 cm³

B100 cm³

C40 cm³

D20 cm³

View Explanation & Discuss

Question 20

waec 2014

Which of the following salts on hydrolysis would give an alkaline solution?

ANH₄CI_(s)

BAICI_3(s)

CCH₃COONa_(s)

DNH₄NO_3(s)

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