Chemistry Exam Past Questions and Answers | JAMB, WAEC and NECO

Chemistry is the study of the substances that make up matter. It looks at their properties, how they react with each other, and how these reactions can create new substances.

• Question 2311: Solutions X, Y, and Z have PH values 3.0. 5. 0 and 9. 0 respectively. Which of the following statements is correct? Options:
  A) All the solutions are acidic
  B) All the solutions are basic
  C) Y and Z are more acidic than water
  D) Y is more acidic than X
  E) Z is the least acidic
  Show Answer
  The correct answer is E .
• Question 2312: When sodium is added to ethanol, the products are? Options:
  A) sodium hydroxide and water
  B) sodium hydroxide and hydrogen
  C) sodium ethoxide and water
  D) sodium ethoxide and hydrogen
  Show Answer
  The correct answer is D .
• Question 2313:

  What is the concentration of a solution containing 2g of NaOH in 100cm3 of solution? [Na = 23, O =16, H = 1]

  Options:
  A) 0.40 moldm${}^{-3}$
  B) 0.50 moldm${}^{-3}$
  C) 0.05 moldm${}^{-3}$
  D) 0.30 moldm${}^{-3}$
  Show Answer
  The correct answer is B .
• Question 2314: Which of the following gases dissolves in water vapour to produce acid rain during rainfall? Options:
  A) Oxygen
  B) Carbon (II) oxide
  C) Nitrogen
  D) Sulphur (IV) oxide
  Show Answer
  The correct answer is D .
• Question 2315: Which of these represents a redox reaction? Options:
  A) AgNO₃ + NaCl → AgCAl + NaNO₃
  B) H₂S + Pb(NO₃) → PbS + 2HNO₃
  C) CaCO₃ → CaO + CO₂
  D) Zn + 2HCl → ZnCl₂ + H₂
  Show Answer
  The correct answer is D .