Classroom

Chemistry Past Questions

Study and practice Chemistry past questions with answers and detailed explanations. Then test your knowledge using our interactive CBT practice platform and prepare confidently for your upcoming examinations.

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

Select subject

Download PHP app Ask a Question Check Syllabus Past Question Videos Topic Video Lessons

Take a test

Custom CBT

Create and set up a CBT environment with your preferred subjects.

JAMB CBT Simulator

Practice JAMB CBT with real UTME past questions in CBT format.

WAEC CBT Practice 2026 Simulator

CB-WASSCE styled past question practice.

NECO CBT Practice 2026 Simulator

SSCE & GCE styled past question practice.

Past Questions

4,306 questions

Question 1 of 20 4,306 total questions

Question 401

waec 2019

which of the following solutions containing one mole per dm\(^3\) of the compound would have the lowest PH?

Aethanoic acid

Bhydrochloric acid

Csodium chloride

Dsodium hydrogentrioxocarbonate(iv)

View Explanation & Discuss

Question 402

waec 2019

Vinegar is an aqueous solution of?

AHydrochloric acid

Bethanedioc acid

Cethanoic acid

Dhydrofluoric acid

View Explanation & Discuss

Question 403

waec 2019

What is the solubility of a salt X at 25ºC if the saturated solution of the salt contains 0.28g in 100cm\(^3\) of the solution in mol\dm\(^3\)?

[ X = 56.0g ]

A0.05

B0.10

C2.60

D2.80

View Explanation & Discuss

Question 404

waec 2019

The properties of a good primary standard solution include the following except?

AHigh molecular mass

Blow molecular mass

Chigh degree of purity

Dreadily available

View Explanation & Discuss

Question 405

waec 2019

The name of the compound CH\(_3\)C(CH\(_3\))\(_2\)CH\(_2\)CH\(_2\)CH\(_3\)

A2 - methyl butane

B2,2 - dimethyl butane

C2 - methyl pentane

D2,2 - dimethyl pentane

View Explanation & Discuss

Question 406

waec 2019

Which of the following compounds has coordinate bonds in its structure?

AAl\(_2\)Cl\(_6\)

BMgCl\(_2\)

CAgCl

DNaCl

View Explanation & Discuss

Question 407

waec 2019

What is the percentage by mass of H in CH\(_3\)COOH ?

A1.7%

B5.0%

C6.7%

D7.1%

View Explanation & Discuss

Question 408

waec 2019

Stoichiometry is based on the law?

Amultiple proportion

Bconstant composition

Cconservation of energy

Dconservation of mass

View Explanation & Discuss

Question 409

waec 2019

How many moles of carbon(iv)oxide contains 16.0g of oxygen?

[ C = 12.0, O = 16.0 ]

A0.20 mol

B0.25 mol

C0.40 mol

D0.50 mol

View Explanation & Discuss

Question 410

waec 2019

When an equilibrium is established between dissolved and undissolved solutes, the solution is said to be?

ASaturated

BUnsaturated

CConcentrated

DDiluted

View Explanation & Discuss

Question 411

waec 2019

Which of the following pairs of components have the same molecular mass?

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

AEthene and Ethyne

BEthane and Ethene

CCarbon (ii) Oxide and Ethene

DCarbon (iv) Oxide and Ethyne

View Explanation & Discuss

Question 412

waec 2019

Which of the substances is non-polar?

ABromine

BAmmonia

CWater

DHydrogen Bromide

View Explanation & Discuss

Question 413

waec 2019

Calcium and magnesium belong to the group of the periodic table because both?

Aare metals

Bform cations

Cform colourless salts

Dhave same number of valence electrons

View Explanation & Discuss

Question 414

waec 2019

If 6.5g of magnesium ribbon reacts completely with Hydrochloric acid, how many grams of hydrogen gas would be liberated?

Mg(s) + 2 HCl(aq) --> MgCl 2(aq) + H 2(g)

[ H = 1.0, Mg = 24.0 ]

A0.54g

B0.70g

C1.08g

D1.40g

View Explanation & Discuss

Question 415

waec 2019

The bleaching action of chlorine is through the process?

AHydration

BHydrolysis

CReduction

DOxidation

View Explanation & Discuss

Question 416

waec 2019

which of the following elements has the highest ionization energy?

ACalcium

BChlorine

CFlourine

DMagnesium

View Explanation & Discuss

Question 417

waec 2019

Which of the following metals reacts slowly with cold water?

AIron

BSilver

CCalcium

DPottassium

View Explanation & Discuss

Question 418

waec 2019

A solid with higher melting and boiling points is likely to be?

ACovalent compound

BA Dative compound

CAn Electrovalent compound

DA Non-metal

View Explanation & Discuss

Question 419

waec 2019

The periodic table is an arrangement of elements according to their?

AOxidation number

BAtomic number

CMass number

DNumber of neutrons

View Explanation & Discuss

Question 420

jamb 2019

Which of the following factors will speed up the rate of evolution of carbon (iv) oxide in the reaction below?
2HCl + CaCO\(_3\) → CaCl\(_2\) + H\(_2\)O + CO\(_2\)

AIncreasing the concentration of the acid

BIncreasing the surface area of CaCO\(_3\)

CA and B

DReducing the concentration of the acid

View Explanation & Discuss

Question Navigator

Current

Chemistry Past Questions

Take a test

Custom CBT

JAMB CBT Simulator

WAEC CBT Practice 2026 Simulator

NECO CBT Practice 2026 Simulator

Past Questions

Question Navigator

MathsFaculty