JAMB Chemistry CBT Practice Test

Practise UTME Chemistry on a computer-based test that works like the real one: timed questions, a navigator to jump between them, and a full review with the correct answer and an explanation for every question.

About these JAMB Chemistry questions

There are 45 questions in this chemistry bank, written by StudentToolsNG to the topics in the JAMB UTME Chemistry syllabus and at the level of the exam. They are original practice questions, not copies of JAMB past papers, so you can practise without memorising old answers.

Each test picks questions at random and shuffles the options, so the answer to a question is not always in the same position. You get 40 seconds a question, the same pace as the UTME, where 180 questions are answered in 2 hours.

Topics covered

The questions cover 20 topics from the syllabus:

• Separation techniques (2 questions)
• The mole concept (3 questions)
• Chemical formulae and equations (2 questions)
• Atomic structure (3 questions)
• Periodic table (2 questions)
• Chemical bonding (3 questions)
• Gas laws and kinetic theory (2 questions)
• Air and water (2 questions)
• Solubility (1 question)
• Environmental pollution (1 question)
• Acids, bases and salts (3 questions)
• Oxidation and reduction (2 questions)
• Electrolysis (2 questions)
• Energy changes (1 question)
• Rates of reaction (1 question)
• Chemical equilibrium (2 questions)
• Non-metals and their compounds (3 questions)
• Metals and their compounds (2 questions)
• Organic chemistry (5 questions)
• Chemistry and industry (3 questions)

Tips for JAMB Chemistry

• Get comfortable with the IUPAC names the UTME uses, such as tetraoxosulfate(VI) for sulfate and trioxocarbonate(IV) for carbonate.
• Mole calculations are the backbone of the paper: moles = mass ÷ molar mass, 22.4 dm³ per mole at s.t.p., and always use the mole ratio from the balanced equation.
• For equilibrium questions, apply Le Chatelier's principle: count the gas moles on each side for pressure and check the sign of ΔH for temperature.
• Memorise the tests for gases and ions (lime water, litmus, glowing splint, flame colours); they are quick marks.

Sample JAMB Chemistry questions with answers

Question 1: Which method is best for separating a mixture of ethanol and water?

A. Filtration B. Fractional distillation C. Evaporation D. Decantation

Answer: B (Fractional distillation). Ethanol and water mix completely but boil at different temperatures (about 78 °C and 100 °C), so fractional distillation separates them.

Question 2: What volume does 0.5 mol of a gas occupy at s.t.p.?

A. 22.4 dm³ B. 11.2 dm³ C. 44.8 dm³ D. 5.6 dm³

Answer: B (11.2 dm³). One mole of any gas occupies 22.4 dm³ at s.t.p., so 0.5 mol occupies 0.5 × 22.4 = 11.2 dm³.

Question 3: An atom has mass number 23 and atomic number 11. How many neutrons does it have?

A. 11 B. 12 C. 23 D. 34

Answer: B (12). Neutrons = mass number − atomic number = 23 − 11 = 12. (This is sodium.)

Question 4: Elements in group 1 of the periodic table are known as the

A. halogens B. noble gases C. alkaline earth metals D. alkali metals

Answer: D (alkali metals). Group 1 (lithium, sodium, potassium…) are the alkali metals. Group 2 are the alkaline earth metals, group 7 the halogens and group 0 the noble gases.

Question 5: Under the same conditions, how many times faster than oxygen does hydrogen diffuse? (H₂ = 2, O₂ = 32)

A. 16 B. 2 C. 4 D. 8

Answer: C (4). Graham's law: rate ∝ 1/√M. Rate(H₂) ÷ rate(O₂) = √(32/2) = √16 = 4.

Question 6: Temporary hardness of water is caused by dissolved

A. calcium tetraoxosulfate(VI) B. sodium chloride C. calcium hydrogentrioxocarbonate(IV) D. magnesium tetraoxosulfate(VI)

Answer: C (calcium hydrogentrioxocarbonate(IV)). Calcium hydrogencarbonate, Ca(HCO₃)₂, breaks down on boiling to insoluble CaCO₃, so the hardness can be removed by boiling. Sulfates cause permanent hardness.

Question 7: What volume of 0.1 mol/dm³ H₂SO₄ neutralises 25 cm³ of 0.1 mol/dm³ NaOH? H₂SO₄ + 2NaOH → Na₂SO₄ + 2H₂O

A. 25 cm³ B. 12.5 cm³ C. 50 cm³ D. 6.25 cm³

Answer: B (12.5 cm³). Moles of NaOH = 0.1 × 25/1,000 = 0.0025. The equation needs half as much acid: 0.00125 mol. Volume = 0.00125 ÷ 0.1 = 0.0125 dm³ = 12.5 cm³.

Question 8: What mass of copper is deposited when 19,300 C of charge passes through copper(II) tetraoxosulfate(VI) solution? (Cu = 64, F = 96,500 C/mol)

A. 12.8 g B. 3.2 g C. 64 g D. 6.4 g

Answer: D (6.4 g). Moles of electrons = 19,300 ÷ 96,500 = 0.2. Cu²⁺ + 2e⁻ → Cu, so 0.2 mol of electrons deposits 0.1 mol of copper = 0.1 × 64 = 6.4 g.

Question 9: For N₂(g) + 3H₂(g) ⇌ 2NH₃(g), ΔH negative, what is the effect of increasing the pressure?

A. The equilibrium shifts to the left B. There is no effect C. The equilibrium shifts to the right D. Only the rate of the backward reaction rises

Answer: C (The equilibrium shifts to the right). There are 4 moles of gas on the left and 2 on the right. By Le Chatelier's principle, higher pressure favours the side with fewer gas moles, so more ammonia forms.

Question 10: Which gas turns damp red litmus paper blue?

A. Chlorine B. Ammonia C. Hydrogen chloride D. Sulfur(IV) oxide

Answer: B (Ammonia). Ammonia is the common alkaline gas. Chlorine bleaches litmus, while hydrogen chloride and sulfur(IV) oxide are acidic and turn blue litmus red.

Question 11: What is the general formula of the alkanes?

A. CₙH₂ₙ B. CₙH₂ₙ₊₂ C. CₙH₂ₙ₋₂ D. CₙH₂ₙ₊₁OH

Answer: B (CₙH₂ₙ₊₂). Alkanes are saturated hydrocarbons, CₙH₂ₙ₊₂ (methane CH₄, ethane C₂H₆). CₙH₂ₙ is the alkenes, CₙH₂ₙ₋₂ the alkynes and CₙH₂ₙ₊₁OH the alkanols.

Question 12: How many structural isomers does butane, C₄H₁₀, have?

A. 1 B. 3 C. 2 D. 4

Answer: C (2). Two: the straight chain (butane) and the branched chain (2-methylpropane).

Frequently Asked Questions

Are these JAMB Chemistry past questions?

No. They are original questions written to the JAMB Chemistry syllabus in the same style and at the same level as the UTME. Practising on new questions shows whether you understand a topic rather than whether you remember an old answer.

How many questions are in the JAMB Chemistry paper?

Each of your three other subjects has 40 questions in the UTME, and Use of English has 60, making 180 questions in 2 hours. That is about 40 seconds a question, which is the pace this practice test uses.

How is JAMB Chemistry scored?

Each subject is scored out of 100 and the four subjects add up to your UTME score out of 400. The percentage you get in this practice test is a rough guide to your score out of 100 in chemistry.

Can I practise without a time limit?

Yes. Choose Study mode to see the correct answer and the explanation as soon as you pick an option, with no timer. Switch to the timed test once you are ready to practise at exam pace.

Other subjects

JAMB Mathematics CBT practice · JAMB Physics CBT practice · JAMB Biology CBT practice