Post Views: 3,644

CHEMISTRY PAST QUESTION

0%

SSCE/NECO/GCE (CHEMISTRY PAST QUESTIONS)

CHEMISTRY PAST QUESTIONS APP

Questions will be picked at random from the question bank.

You can use the NEXT button to move to the next question, use the PREV button to move to the previous question, the CLEAR button to clear any answer of your choice and you have the FINISH button to end the exam if you choose to.
Any question not answered before the end of the exam time, will be marked as wrong and the exam will end by itself. so try to attempt all questions on time.
Goodluck!

1 / 80

Category: CHEMISTRY PAST QUESTIONS

What is the shape of a molecule of CCI₄?

Linear

Tetrahedral

Pyramidal

Trigonal planar

2 / 80

Category: CHEMISTRY PAST QUESTIONS

A reaction is represented by the equation below. A_2(g) + B_2(g) 2AB_(g); ∆H = +X kJmol^-1 Which of the following statements about the system is correct?

Pressure has no effect on the equilibrium mixture

The forward reaction is exthermic

The reaction goes to completion at equilibrium

At equilibrium increase in temperature favours the reverse reaction

3 / 80

Category: CHEMISTRY PAST QUESTIONS

Dehydration of ethanol produces

propan-1,2,3-triol

ethanoic acid

ethanal

ethene

4 / 80

Category: CHEMISTRY PAST QUESTIONS

If an element with high electron affinity combines with another element with low ionization energy the bond formed will be mainly

covalent

ionic

metallic

dative

5 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following increases as boiling water changes to steam?

number of molecules

activation energy

temperature of the system

degree of disorder in the system

6 / 80

Category: CHEMISTRY PAST QUESTIONS

A concentrated solution containing H⁺, Cu²⁺,OH^- and CI^- was electrolysed using platiunm electrodes which of the ions will be discharged at the cathods?

H+

Cu2+

CI-

OH-

7 / 80

Category: CHEMISTRY PAST QUESTIONS

What type of reaction is involved when wood shavings produce a brown gas with concentrated HNO₃?

Redox reaction

Dehydration

Destructive distillation

Nutralization

8 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following properties increases down a group in the Periodic Table?

Ionization energy

Atomic radius

Electronegativity

Electon affinity

9 / 80

Category: CHEMISTRY PAST QUESTIONS

A mixture of calcium chloride and calcium trioxocarbonate (IV) in water can be separated by

distillation

sublimation

evaporation

filtration

10 / 80

Category: CHEMISTRY PAST QUESTIONS

One mole of a compound M(HCO₃)₂ has a mass of 162g. Calculate the relative atomic mass of M. [H = 1, C =12, O = 16]

101

122

40

53

11 / 80

Category: CHEMISTRY PAST QUESTIONS

How many electrons are removed from Cr^2- when it is oxidized to CrO₄^2-?

0

4

8

2

12 / 80

Category: CHEMISTRY PAST QUESTIONS

If the solubility of KHCO₃ is 0.40 mole dm^-3

40.0g

100.0g

10.0g

4.0g

13 / 80

Category: CHEMISTRY PAST QUESTIONS

What is oxidized in the reaction represented by the following equation? 3CU + 8HNO₃ → 3Cu(NO₃)₂ + 2NO + 4H₂O

Nitrogen

Oxygen

Hydrogen

Copper

14 / 80

Category: CHEMISTRY PAST QUESTIONS

Two radioactive elements Q and S have half-life periods of 10 hours and 20 hours respectively. Therefore

S is more stable than Q

S decays faster than Q

Q is twice as stable as S

Q emits fewer particles than S

15 / 80

Category: CHEMISTRY PAST QUESTIONS

Helium is preferred to hydrogen in filling balloons because hydrogen

is a component of water

is inflammable

exhibits isotopy

is diatomic

16 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following compounds dissolves in water to form a solution with pH below 7?

Sodium tetraoxosulphate (VI)

Potassium hydroxide

Ammonium chloride

Sodium trioxocarbonate (IV)

17 / 80

Category: CHEMISTRY PAST QUESTIONS

Consider the reaction represented by the following equation: H_2(g) + 1_2(g) → 2HI_(g). The number of effective collisions of molecules of the reactants decreases as

the pressure increased

the temperature is raised

the volume of the system is increased

a catalysty is intoduced into the system

18 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following occurs when a solution of CuSO₄ is electrolysed using copper electrodes?

Both electrodes gain electrons

The blue colour of the solution fades gradually

The cathode becomes coated with copper

The anode increases in mass

19 / 80

Category: CHEMISTRY PAST QUESTIONS

Chemical equilibrium is attained when

concentrations of the reactants and products remain constant

reactants stop forming the products

concentrations of the products are greater than those of the reactants

reactants in the system are used up

20 / 80

Category: CHEMISTRY PAST QUESTIONS

When alkanols react with sodium, the ga evolved is

methane

ethyne

oxygen

hydrogen

21 / 80

Category: CHEMISTRY PAST QUESTIONS

A finely divided from of a metal burns more readily in air than the rod from because the rod has

different chemical properties

protective oxide coating

higher molar mass

smaller surface area

22 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following non-metals reacts most readily with metals?

Chlorine

Carbon

Nitrogen

Sulphur

23 / 80

Category: CHEMISTRY PAST QUESTIONS

P _Total = F₁ + P₂ + P ₃ + .........P_n' where P _Total is the pressure of a mixture of gasses. The equation above is an expression of

Dalton's law

Boyle's law

Graham's law

Gay-Lussac's Law

24 / 80

Category: CHEMISTRY PAST QUESTIONS

A radioactive solid is best stored

in a cool, dark cupboard

in a box lined with lead

under paraffin oil

under ultraviolet light

25 / 80

Category: CHEMISTRY PAST QUESTIONS

0.10 mol dm^-3 NaCI conducts electricity better than 0.10 mol dm^-3 CH₃COOH because the solution of NaCI

has a lower molar mass

contains more ions

has a higher pH

is neutral to litmus

26 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following pairs of reagents recat to produce hydrogen?

Magnesium and dilute tetraoxosulphate (VI) acid

Water and calcium dicarbide

Zinc and concentrated trioxonitrate (V) acid

Copper and dilute hydrochloric acid

27 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following can undergo both addition reactions and substitution reactions?

Propene

Hexane

Benzene

Pentane

28 / 80

Category: CHEMISTRY PAST QUESTIONS

Gas molecules are said to be perfectly elastic because

the distances between them are negligible

they move about in straight lines

the volume occupied by them is negligible

they collide without loss of energy

29 / 80

Category: CHEMISTRY PAST QUESTIONS

The spontaneity of a chemical reaction is determined by the change in the

pressure applied to the system

free energy of the system

concentration of the reactants

temperature of the system

30 / 80

Category: CHEMISTRY PAST QUESTIONS

Exhaust fumes discharged from a smoky vehicle gradually become invisible as a result of

emission

absorption

diffusion

combustion

31 / 80

Category: CHEMISTRY PAST QUESTIONS

In the Periodic Table, the elements that loss electrons most readily belong to

Group 11 A

Group 1 A

Group 111 A

Group V11 A

32 / 80

Category: CHEMISTRY PAST QUESTIONS

The liquid product of the destructive distillation of coal is

paraffin oil

kerosene

ammoniacal liquor

ethanol

33 / 80

Category: CHEMISTRY PAST QUESTIONS

It can be concluded that gastric juice

contains enzymes

has pH value of 7

is acidic

is a mixture

34 / 80

Category: CHEMISTRY PAST QUESTIONS

Petrol consists mainly of

hydrocarbons

polymers

alkanoates

alktanols

35 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following procedures is suitable for identifying the food colouring added to a pastry sample?

The blue colour of the solution fades gradually

The anode increases in mass

The cathode becomes coated with copper

Both electrodes gain electrons

36 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following statements about ideal gases is/are correct?
I. The cohesive forces between their particles are negligible
ll. The have no definite volume but occupy the volume of their containers
III. They are not compressible
IV. Their particles collide with loss of energy

l, ll, lll, and IV

l only

l, ll and lll only

l and ll only

37 / 80

Category: CHEMISTRY PAST QUESTIONS

What is responsible for metallic bonding?

transfer of electrons from one atom to another

Attraction between positive and negative ions

Attraction between the atomic unclei and cloud of electrons

Sharing of electrons between the metal atoms

38 / 80

Category: CHEMISTRY PAST QUESTIONS

Given that the order of reactivity of four metals is P>Q>R>S, which of the following reactions is feasible?

S + P+ → P + S +

R + P+ → P + R+

S + Q+ → Q + S+

Q + S+ → S + Q+

39 / 80

Category: CHEMISTRY PAST QUESTIONS

Calcium atom ionizes by

losing two electrons

gaining two electrons

gaining two protons

sharing two electrons

40 / 80

Category: CHEMISTRY PAST QUESTIONS

What is the value of x in the following equation? Cr₂O₇^2- + 14H⁺ + xe- → 2Cr³⁺ + 7H₂O

6

1

8

12

41 / 80

Category: CHEMISTRY PAST QUESTIONS

What mass of copper would be deposited by a current of 1. 0 ampere passing for 965 seconds through copper (ll) tetraoxosulphate (IV) solution? [Cu = 63.5; 1F = 96500C]

0.318g

6.35g

0.635g

18g

42 / 80

Category: CHEMISTRY PAST QUESTIONS

Rusting of iron is an example of

deliquescence

displacement reaction

redox reaction

decomposition

43 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following will displace copper from a solution of copper (ll) salt?

Aluminium ions

Silver

Magnesium

Zinc ions

44 / 80

Category: CHEMISTRY PAST QUESTIONS

Pauli Exclusion Principle is related to

reversiblility of equlibrium reactions

collision theory of reaction rates

electronegativity values of elements

quantum numbers of electrons

45 / 80

Category: CHEMISTRY PAST QUESTIONS

Aluminium is extracted from

magnetite

cryolite

cassiterite

bauxite

46 / 80

Category: CHEMISTRY PAST QUESTIONS

The atoms of four elements are represented as ₂₀Q, ₁₆R, ₁₀S and ₈T Which of the elements would be unreactive?

T

Q

R

S

47 / 80

Category: CHEMISTRY PAST QUESTIONS

Chlorine atom forms CI by

Losing one electron

Donating lone pair of electrons

Gaining one electron

Sharing one electron

48 / 80

Category: CHEMISTRY PAST QUESTIONS

What volume of hydrogen is produced at s.t.p. When 2.60 g of zinc reacts with excess HCI according to the following equation? Zn_(s) + 2HCI_(aq) → ZnCI _2(aq) + H_2(g) [Zn = 65; 1 mole of a gas occupies 22.4dm³ at s.t.p]

5.82dm 3

8.62dm 3

0.040dm 3

0.896dm 3

49 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the orbitals 4s, 4p, 4d and 4f has the lowest energy?

4f

4s

4d

4p

50 / 80

Category: CHEMISTRY PAST QUESTIONS

What is the oxidation number of nitrogen in AI(NO₃)₃?

+ 1

+ 6

+ 3

+ 5

51 / 80

Category: CHEMISTRY PAST QUESTIONS

Substances which absorb water from the atmosphere without dissolving in it are said to be

hygroscopic

anhydrous

hydrated

insolube

52 / 80

Category: CHEMISTRY PAST QUESTIONS

Pipe-borne water is usually chlorinated in order to

kill harmful bacteria in the water

coagulate sediments in the water

improve the teste of the water

remove the hardness in the water clear

53 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following lowers the activation energy of a chemical reaction?

Freezing mixture

Water

Catalyst

Reducing agent

54 / 80

Category: CHEMISTRY PAST QUESTIONS

The type of chemical bond that exists between potassium and oxygen in potassium oxide is

covalent

ionic

metallic

dative

55 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following movements can be described as random motion?

planets going round the sun

car travelling on a straight line

wheelbarrow being pushed

gas molecules colliding in a flask

56 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following compounds dissolves in water to give an alkaline solution?

Ammonium chloride

Sulphur (IV) oxide

Potassium oxide

Sodium chloride

57 / 80

Category: CHEMISTRY PAST QUESTIONS

The crystal layers in graphite are held together by

covalent bonds

electrostatic forces

hydrogen bonds

van der Waals' forces

58 / 80

Category: CHEMISTRY PAST QUESTIONS

30cm³ pf hydrogen at s.t.p combine with 20cm³ of oxygen to form steam according to the following equation 2H_2(g) + O_2(g) → 2H₂O_(g). Calculate the total volume of the gaseous mixture at the end of the reaction

30cm cube

50cm cube

25cm cube

35cm cube

59 / 80

Category: CHEMISTRY PAST QUESTIONS

Elactrostatic force of attraction between sodium ion and halide ion is greatest in

NaCI

NaF

NaI

NaBr

60 / 80

Category: CHEMISTRY PAST QUESTIONS

Consider the following equation: Ag⁺ _(aq) + CI-_(aq) → Ag⁺CI- _(s) ; ∆H = _65.7 kJmol^-1. From the equation, it can be deduced that

direct combination is involved and the reaction is endothermic

activation energy is high and a catalyst is required

the reaction is endothermic and occurs at high temperature

a solid is formed and heat is evolved

61 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following methods is suitable for the preparation of an insoluble salt?

Double decomposition

Action of an acid on a metal

Action of an acid on a trioxocarbonate (IV)

Neutralisation

62 / 80

Category: CHEMISTRY PAST QUESTIONS

What is the effect of using vanadium (V) oxide as catalyst in the reaction represented by the following equation? 2SO₂ + O₂ ⇌ 2SO₃; ∆H = - xKJmol-¹

Decreases the value of ∆H

Reduces the time for attainment of equilibrium

Increases the collision rate of reactant particles

Shifts equilibrium position to the right

63 / 80

Category: CHEMISTRY PAST QUESTIONS

Equal volumes of CO₂ cnd CO at s.t.p have the same

number of molecules

rate of diffusion

density

mass

64 / 80

Category: CHEMISTRY PAST QUESTIONS

What will be the effect of increase in pressure on the following system at equilibrium? 2NH_2(g) N_2(g) + 3H_2(g)

the forward reaction will be favoured

Activation energy will decrease

the concentration of ammonia will increase

the reaction will go to completion

65 / 80

Category: CHEMISTRY PAST QUESTIONS

Elements which belong to the same group in the Periodic Table are characterized by

difference of +1 in the oxidation numbers of successive members

difference of 14 atomic mass units between successive members

presence of the same number of electron shells in the respective atoms

presence of the same number of outermost electrons in the respective atoms

66 / 80

Category: CHEMISTRY PAST QUESTIONS

Metals are said to be malleable because they

are good conductors heat

are good conductors of electricity

can be alloyed

can be beaten into sheets

67 / 80

Category: CHEMISTRY PAST QUESTIONS

An exothermic reaction is one which involves

loss of heat to the surrounding

attainment of dynamic equilibrium

positive change in value of enthalpy

evolution of gas as it proceeds

68 / 80

Category: CHEMISTRY PAST QUESTIONS

What is the function of sulphur (IV) oxide in the reaction represented by the following equation? SO _2(aq) + 2H₂S_(g) → 3S _(s) + 2H ₂O _(l)

Oxidising agent

Dehydrating agent

Acid

Bleaching agent

69 / 80

Category: CHEMISTRY PAST QUESTIONS

The property of calcium chloride which makes it useful as a drying agent is that it is

ionic

deliquescent

a normal salt

a strong electrolyte

70 / 80

Category: CHEMISTRY PAST QUESTIONS

The presence of unpaired electrons in an atom of a transition metal gives rise to

shiny appearance

ductility

nalleability

paramagnetism

71 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following contains co-ordinate covalent bond?

NH4

HCI

Na+CI

CH4

72 / 80

Category: CHEMISTRY PAST QUESTIONS

What does ∆H represent in the following equation ? Cl_(g) + e- → CI- _(g); ∆H = - 363 kJ mol-¹

Dissociation energy

Electron affinity

lonization energy

Heat of atomization

73 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following will produce oxygen and hydrogen during its electrolysis using platinum electrode?

Concentrated hydrochloric acid

Dilute sodium chloride solution

Glucose solution

Aqueous copper (ll) tetraoxosulphate (IV)

74 / 80

Category: CHEMISTRY PAST QUESTIONS

Electrovalent compounds are characterized by

high molar mass

solubility in ethanol

high melting point

strong oxidizing ability

75 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following features of a human skeleton can be determined by carbon-dating?

Mass

Race

Age

Height

76 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following is not correct about oxidation number convention? The oxidation number of a/an

monatomic ion is equal to its charge

atom of a diatomic molecules is + 2

alkali meta like sodium in its compounds is + 1

element in the free state is zero

77 / 80

Category: CHEMISTRY PAST QUESTIONS

A sheet of paper is placed in the path of a beam from a radioactive source. The emissions that pass through the paper consist of

alpha particles only

alpha and beta particles

beta particles and gamma rays

alpha particles and gamma rays

78 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following substances decomposes when an electric current is passed through it?

Glucose solution

Tetrachlormethane

Zinc rod

Hydrochloric acid

79 / 80

Category: CHEMISTRY PAST QUESTIONS

The gas evolved when dilute tetraoxosulphate (VI) acid reacts with sodium hydrogen trioxocarbonate (IV) is

carbon (IV) oxide

sulphur (VI) oxide

hydrogen

oxygen

80 / 80

Category: CHEMISTRY PAST QUESTIONS

Which of the following would dissolve in warm dilute H₂SO₄ without effervescence, to give a blue solution?

Copper (ll) trioxocarbonate (IV)

Copper (ll) oxide

Copper turnings

Copper alloy

Your score is
0%

SUBSCRIBE BELOW FOR A GIVEAWAY

More Suggestions

Menu ↓↓↓

Home Subjects Past Questions Topics Scholarships Search Box