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Chemistry Past Questions

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33 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Past Questions

33 questions

Question 1 of 13 33 total questions

Question 11

waec 1993

Which of the following pieces of deposited if a current of 10A was passed through a solution of copper(ll) salt for 965 seconds? (1F = 96500 C)

A0.005 mole

B0.025 mole

C0.05 mole

D1.00 mole

E1.05 mole

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Question 12

waec 1993

Chlorine is is used in water treatment as

Aa germicide

Ba decolorizing agent

Can antioxidant

Da coagulating agent

Ean aerating agent

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Question 13

waec 1993

In which of the following changes is ∆S negative ?

AH₂O_(l) → H₂O_(s)

BC_(s) + 1/2O_{2,/sub>_(g) → CO_(g)}

CPCI₅_(g) → PCl₃_(g) + Cl₂_(g)

DNaCl_(s) + aq →Na₊ _(aq) + Cl_- _(aq)

ENH₃_(g) + HCl_(g)

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Question 14

waec 1993

Sulphur burns in air to form

Aan acidic oxide

Ba basic oxide

Can amphoteric oxide

Da neutra oxide

Ea mixed oxide

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Question 15

waec 1993

What does X atand for in the following expression? X = Log₍₁₀₎(H⁺)

AEnthalpy change (∆H)

BEquilibrium constant (K)

CSolubility product

DDegree of acidity (pH)

Elonic product of water

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Question 16

waec 1993

Carbon is often deposited in the exhaust-pipe of cars because of the?

Apresence of carbon in petrol

Bdehydrogenation of petrol

Cincomplete combustion of petrol

Dpresence of additives in petrol

Econtamination of petrol with diesel

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Question 17

waec 1993

Which of the following pairs illustrates isotopy?

ABut-l-ene and but -2-ene

BOrtho-hydrogen and parahydrogen

COxygen and ozone

DHydrogen and deuterium

EAlpha-particle and beta-particle

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Question 18

waec 1993

Alkanes are used mainly

Ain the production of plastics

Bas domestic and industrial fuels

Cin the textile industry

Din the hydrogenation of oils

Eas fine chemicals

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Question 19

waec 1993

Trioxosulphate (lV) acid is not stored for a long period because it

Ais a weak dibasic acid

Bhas bleaching properties

Cis unstable and eaily decomposed

Dsmells strongly of sulphur (lV) oxide

Ecan act as a germicide

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Question 20

waec 1993

Which of the following solids has a network structure?

ADiamond

Blodine

CSulphur

DGraphite

Elron

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Question 21

waec 1993

Starch undergoes complete hydrolysis to produce

Amaltose

Blactose

Cfructose

Dglucose

Esucrose

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Question 22

waec 1993

Which of the following separation is routinely applied in the petroleum industry

AFiltration

BChromatography

CEvaporation

DFractional crystallization

EFractional distillation

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Question 23

waec 1993

Copper metal will react with concentrated trioxonitrate (V) acid to give?

ACu(NO₃)₃ + NO + N₂O₄ + H₂O

BCu(NO₃)₂ + NO + H₂O

CCuO + NO₂ + H₂O

DCu(NO₃)₂ + 2NO₂ + 2H₂O

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