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Chemistry Past Questions

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91 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Past Questions

91 questions

Question 1 of 20 91 total questions

Question 11

waec 2013

When heat is absorbed during a chemical reaction, the reaction is said to be

Aadiabatic

Bendothermic

Cexothermic

Disothermal

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Question 12

waec 2013

Which of the following variables is a measure of the average kinetic energy of the molecule of a gas?

ADensity

BPressure

CTemperature

DVolume

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Question 13

waec 2013

Which of the following gases are arranged in increasing order of diffusion rate? [H = 1 .0; C = 12; N = 14; O = 16; S = 32]

ASO ₂ O₂, NH₃ H₂

BH₂S,NH₂,O₂,SO₂

CCO₂,N₂O,O₂,SO₂

DNH₃,NO₂,N₂,CO₂

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Question 14

waec 2013

The pressure exerted by a gas is a function of the

Atotal volume of the gas

Bspeed of the gaseous molecules

Cmass of each gaseous molecule

Dfrequency of collision between gaseous molecules

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Question 15

waec 2013

Which of the following phenomenna lead to decrease in volume of a liquid in an open container?

ABrownian motion

BDiffusion

CEvaporation

DSublimation

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Question 16

waec 2013

The gas law which describes the relationship between volume and temperature is

ABoyle's law

BCharles' law

CDalton's law

DGraham's law

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Question 17

waec 2013

The percentage by mass of calcium in Ca(OCI)2 is [Ca = 40.0; CI = 35.5; O = 16.0]

A28.0%

B31.6%

C43.8%

D44.5%

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Question 18

waec 2013

The volume of 0.25 moldm-3 solution of KOH that would yield 6.5g of of solid KOH on evaporation is (K = 39.0; o = 16.0; H = 1.00)

A464.30 cm³

B625.00 cm³

C1000.00 cm³

D2153.80 cm³

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Question 19

waec 2013

Consider the reaction represented by the following equation: C\(_2\)H\(_2\) + yH\(_2\) → C\(_2\)H\(_6\). The value of y in the reaction is

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Question 20

waec 2013

Which of the following statements about nuclear reaction is correct? The reaction

Ainvolves neutrons only

Btakes place inside the nucleus

Cis governed by temperature and pressure

Dinvolves protons and electrons only

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Question 21

waec 2013

Noble gas molecules are held together by

Avan der Waals forces

Bhydrogen bonds

Cdative bonds

Dcovalent bonds

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Question 22

waec 2013

Which of the following elements is diatomic?

ASodium

BOxygen

CIron

DNeon

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Question 23

waec 2013

The bonds in crystalline ammonium chloride are

Acovalent and dative

Bionic and covalent

Cionic, covalent and dative

Dionic, covalent and hydrogen bond

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Question 24

waec 2013

In metallic solid, the forces of attraction is between the mobile valence electrons and the

Aatoms

Bneutrons

Cnegative ions

Dpositively charged nuclei

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Question 25

waec 2013

Which of the following bond types is responsible for the high boiling point of water?

AMetallic bond

BCovalent bond

Clonic bond

DHydrogen bond

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Question 26

waec 2013

In which of the following series are the atoms arranged in order of increasing ionization energy?

ALi, Na K

BB, Be, Li

CO, F, Ne

DBe, mG, Ca

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Question 27

waec 2013

In the periodic table, alkaline earth metals can be found in group

Bll

CVI

DVII

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Question 28

waec 2013

Rare gases are stable because they

Aare chemically active

Bcontain equal number of protons and neutrons

Ccontain more electrons than protons

Dhave octet structures

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Question 29

waec 2013

Which of the following halogens is liquid at room temperature?

Alodine

BChlorine

CBromine

DFluorine

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Question 30

waec 2013

In the periodic table all elements within the same group have the same

Anumber of neutrons

Bnumber of valence electrons

Cnumber of isotopes

Datomic number

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