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Chemistry Past Questions

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90 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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90 questions

Question 1 of 20 90 total questions

Question 21

waec 2021

Which of the graphs illustrates the variation of the pH of a given volume of strong acid solution (y-axis) with the volume of strong base titrated against its (x-axis)?

BII

CIII

DIV

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Question 22

waec 2021

Which of the following illustrates the variation of the rate of evolution of gas from a given length of magnesium ribbon (y-axis) with an increase in the concentration of the added (x-axis)?

BII

CIII

DIV

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Question 23

waec 2021

Which of the following pairs of compounds would form a precipitate when their aqueous solutions are mixed?

ANaCl and KNO\(_{3}\)

BKCL and NaNO\(_{3}\)

CK\(_{2}\)SO\(_{4}\) and BaCl\(_{2}\)

DNH\(_{4}\)NO\(_{3}\) and CO\(_{3}\)

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Question 24

waec 2021

The alkanol represented by the structure above is

Aprimary and dihydric

Bsecondary and monohydric

Ctertiary and dihydric

Dsecondary and dihydric

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Question 25

waec 2021

If humid air is polluted by chlorine discharged, the air can be restored by sprinkling

Asolid MnO\(_{2}\)

Bacidified KMnO\(_{4}\)

Cacidified FeSO\(_{4}\)

Dsaturated NaCl(aq)

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Question 26

waec 2021

Cathodic protection of metals is based on

Astandard electrode potential of hydrogen

Bits electrical conductivity

Cnature of oxides formed

Drelative tendencies of oxidation

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Question 27

waec 2021

What is the relative molecular mass of the compound below?

What is the relative molecular mass of the compound below [H = 1.0; C = 12.0; O = 16.0] - SchoolNGR

[H = 1.0; C = 12.0; O = 16.0]

A137

B136

C64

D59

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Question 28

waec 2021

The ratio of carbon atoms of hydrogen atoms in a hydrocarbon is 1:2. If its molecular mass is 56, what is its molecular formula?

AC\(_{3}\)H\(_{6}\)

BC\(_{4}\)H\(_{8}\)

CC\(_{2}\)H\(_{4}\)

DCH\(_{2}\)

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Question 29

waec 2021

Which of the following oxide causes acid rain?

ACO

BNO

CH\(_{2}\)O\(_{2}\)

DNO\(_{2}\)

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Question 30

waec 2021

The hydrolysis of proteins by diluting mineral acids produces

Asucrose

Bglucose

Camino acids

Dfatty acids

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Question 31

jamb 2021

The process by which salt and water reacted in a limited way to form an acid or a base is?

ANeutral process

BBasic acidic process

CHydrolysis

DSublimation

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Question 32

jamb 2021

The fourteen elements (atomic number 90-103) after actinium are called?

AActinoids

BNucleotides

CPre-actinum elements

DAtomic elements

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Question 33

jamb 2021

The molar enthalpy change accompanying the removal of an electron from a gas phase atom or ion in its ground state is called?

AElectron gain enthalpy

BIonization enthalpy

CEnthalpy change

DEnthalpic gas removal

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Question 34

jamb 2021

In troposphere, the two types of pollutants are?

AGaseous and particulate pollutants

BCarbon and metallic pollutants

CNatural and man-made pollutants

DSulphuric and nitrogenous pollutants

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Question 35

jamb 2021

One of the following is not a physical property of monosaccharides?

AMonosaccharides get charred when heated

BMonosaccharides are water-soluble, sweet substances

CThey are highly vital to the exploration of metals

DThey can be reduced to sugar alcohols

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Question 36

jamb 2021

The compounds made up of only carbon and hydrogen are called?

ACarbon compounds

BHydrocarbons

CAtoms

DCarbon hydrolysis

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Question 37

jamb 2021

The process or act of extracting a metal from its ore and refining it is called?

AExtraction

BMetal mining

CMettallurgy

DProspecting

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Question 38

jamb 2021

A binary compound of oxygen with another element is referred to as?

AOxide

BElement

CCarbon

DNitrogen

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Question 39

jamb 2021

The reactions involving simultaneous oxidation and reduction?

AAutomatic reactions

BAlternate reactions

CReduction agency

DRedox reactions

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Question 40

jamb 2021

A chemical process in which there is a gain of electrons is known as?

ASublimation

BReduction

COxidation

DDistillation

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