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Chemistry Past Questions

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4,306 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Past Questions

4,306 questions

Question 1 of 20 4,306 total questions

Question 671

jamb 2015

When salt loses its water of crystallization to the atmosphere on exposure, the process is said to be

Aefflorescence

Bdéliquescence

Ceffervescence

Dfluorescence

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Question 672

jamb 2015

A small quantity of solid ammonium chloride (NH4Cl) heated gently in a test tube, the solid gradually disappear produce two gases. Later, a white cloudy deposit was absence on the cooler part of the test tube. The ammonium chloride is to have undergo

Adistillation

Bsublimation

Cprecipitation

Devaporation

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Question 673

jamb 2015

The acid in electrolysis of water is dilute

AHNO₃

BCH₃COOH

CH₂SO₄

DHCl

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Question 674

jamb 2015

Vulcanization involve the removal of

Amonometer

Bthe single bond

Cthe double bond

Da polymer

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Question 675

jamb 2015

The gas that is most useful in protecting humans against solar marathon is

Achlorine

Bozone

Ccarbon IV oxide

Dhydrogen sulphide

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Question 676

jamb 2015

In the industrial production of H2 from water gas the CO2 produced along with the H2 is removed by

Awashing under pressure

Bdrying over phosphorus (V) oxide

Cpassing the mixture to the limewater

Dusing ammonical copper (I) chlorine

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Question 677

jamb 2015

Iron is often galvanized in order to

AMake it more malleable

BRemove the impurities unit

CProtect it against corrosion

DRender it passive

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Question 678

jamb 2015

Which of these require crystallization most?

ADrug making

BCement making

CPaint making

DPerfume making

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Question 679

jamb 2015

The filter in the cigarette reduce the nicotine construct by

Aburning

Badsorption

Cevaporation

Dabsorption

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Question 680

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 681

waec 2014

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

Acatalysis

Belectrolysis

Coxidation

Dreduction

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Question 682

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 683

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 684

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 685

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 686

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 687

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 688

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 689

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 690

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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