Skip to content

WAEC WASSCE 2023

WAEC Chemistry 2023 past questions

5 objective questions from the 2023 WAEC Chemistry paper. Answer each one, then reveal the answer and explanation.

All WAEC Chemistry past questions

  1. Question 1

    Electronic configuration

    What is the electronic configuration of beryllium (atomic number 4)?

    1. Option A: 2, 1
    2. Option B: 2, 3
    3. Option C: 2, 2
    4. Option D: 2, 4
    Show the answer to question 1

    Answer: C, 2, 2

    Fill the shells in order, 2 then 8 then 8: beryllium has 4 electrons, arranged 2, 2.

  2. Question 2

    Atomic structure

    An atom of nitrogen has atomic number 7 and mass number 14. How many neutrons are in its nucleus?

    1. Option A: 7
    2. Option B: 14
    3. Option C: 21
    4. Option D: 8
    Show the answer to question 2

    Answer: A, 7

    Neutrons = mass number − atomic number = 14 − 7 = 7.

  3. Question 3

    Chemical symbols

    What is the chemical symbol of antimony?

    1. Option A: Sb
    2. Option B: An
    3. Option C: A
    4. Option D: At
    Show the answer to question 3

    Answer: A, Sb

    Antimony is Sb, from its Latin name stibium.

  4. Question 4

    Gas laws

    A fixed mass of gas occupies 480 cm³ at a pressure of 3 atm. What volume will it occupy at 2 atm if the temperature stays constant?

    1. Option A: 320 cm³
    2. Option B: 480 cm³
    3. Option C: 720 cm³
    4. Option D: 2880 cm³
    Show the answer to question 4

    Answer: C, 720 cm³

    By Boyle's law, P₁V₁ = P₂V₂, so V₂ = 3 × 480 ÷ 2 = 720 cm³.

  5. Question 5

    Organic chemistry

    What is the molecular formula of propene?

    1. Option A: C₃H₆
    2. Option B: C₃H₈
    3. Option C: C₃H₄
    4. Option D: C₃H₇
    Show the answer to question 5

    Answer: A, C₃H₆

    Alkenes follow CₙH₂ₙ, so propene with 3 carbon atoms is C₃H₆.

Practise WAEC Chemistry on SchoolEasy CBT

In SchoolEasy, students answer timed questions on screen, see an explanation for every answer, and track their progress topic by topic. Teachers turn past questions into class tests that mark themselves.

School management made effortless.

We strive to build the best school management software for schools from all over the world.

Available soon on all digital platforms

Download on theApp StoreGet it onGoogle Play