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Chemistry Past Questions

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87 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Past Questions

87 questions

Question 1 of 20 87 total questions

Question 11

waec 2005

NaHCO_3(s) can be distinguished from Na₂CO_3(s) by the action of

Adilute hydrochloric acid

Bcarbon (IV) oxide

Caqueous ammonia

Dheat

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Question 12

waec 2005

Which of the following is not an acid anhydride?

AP ₂O ₅

BNO ₂

CSO ₂

DCO

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Question 13

waec 2005

HNO3 does not usually react with metals to liberate hydrogen because HNO3 is

Aa strong acid

Ba corrosive acid

Can oxidizing agent

Da nitrating agent

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Question 14

waec 2005

Which of the following statements is not a postulate of the kinetic theory of gases?

AMolecules move with the same speed

Bintermolecular forces are negligible

CMolecules are in a state of constant random motion

Dcollision between molecules is elastic

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Question 15

waec 2005

When X is heated with manganese (IV) oxide, oxygen is produced X is

AKCI

BKCIO₃

CCaCO₃

DZnCO₃

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Question 16

waec 2005

Which of the following factors does not affect the rate of reaction of CaCO₃ with HCI?

Atemperature of the reaction

Bsolubility of the CaCO₃

Cconcentration of the HCI

Dsurface area of the CaCO₃

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Question 17

waec 2005

The activation energy of a reaction can be altered by

Aadding a reducing agent

Bapplying a high pressure

Cusing a catalyst

Dchanging the temperature

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Question 18

waec 2005

In which of the following reactions is the position of equilibrium not affected by an increase in pressure?

A3Fe_(s) + 4H₂O_(g) ⇌ Fe₃O_4(s) + 4H_2(g)

B2NO_2(g) ⇌ N₂O _4(g)

C3H_2(g) + N_2(g) ⇌ 2NH_3(g)

D2SO_2(g) + O_2(g) ⇌ 2SO_3(g)

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Question 19

waec 2005

The volume occupied by a given mass of gas depends on its

Adiffusion rate

Btemperature and pressure

Cdegree of solubility

Drelative density

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Question 20

waec 2005

Which of the following molecules has a linear structure?

ANH₃

BH₂O

CCO₂

DCH₄

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Question 21

waec 2005

Which of the following can be used to predict the type of bonding in HCI?

ApH value

BElectronegativity difference

CHeat of neutralization

DHeat of solution

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Question 22

waec 2005

An element which can exist in two or more forms in the same physical state, exhibits

Aisotopy

Bstructural isomerism

Callotropy

Dvariable valency

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Question 23

waec 2005

An element X has an atomic number of 16. What is its most likely oxidation state in its binary compounds?

A-3

B-2

C+2

D+4

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Question 24

waec 2005

Which of the following changes is characteristic of an alpha-particle emission?

Athe nucleus loses two protons and two neutrons

Ba proton combines with an electron giving off heat

Cthe nucleus splits into two equal parts

Dfour neutrons are lost

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Question 25

waec 2005

Which of the following sets of elements are arranged in order of decreasing atomic size in the Periodic Table?

A₆C, ₄Be, ₇N,₈ O

B₄Be,₆ C,₇ N,₈ O

C₈O, ₇ N, ₆C, ₄Be

D₇N, ₈O, ₆C,₄Be

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Question 26

waec 2005

What is the mass number of an element having 20 neutrons, 15 protons and 15 electrons?

A15

B30

C35

D50

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Question 27

waec 2005

The electronic configuration of an element X is 1s²2s ²2s⁶3p ² 3p⁴. It can be deduced that X

ABelongs to group 6 of the Periodic Table

BBelongs to group IV of the Periodic Table

Chas 3 unpaired electrons in its atom

Dhas relative molecular mass of 16

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Question 28

jamb 2005

The IUPAC nomenclature for the hydrocarbon above is

A1,2 - dimethylprop-2-ene

B1,1- dimethylprop-2-ene

C2-methylbut-3-ene

D3-methylbut-1-ene

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Question 29

jamb 2005

To obtain pure carbon (II) oxide from its mixture with carbon (IV) oxide, the mixture should be

Apassed over heated copper (II) oxide

Bbubbled through water

Cbubbled through concentrated tetroxosulphate (VI) acid

Dbubbled through sodium hydroxide

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Question 30

jamb 2005

Which of the following alloys contain iron?

ADuralumin and steel

BBrass and bronze

CSteel and permalloy

DSoft solder and duralumin

View Explanation & Discuss

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