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 101: The gasification of coke is used for the manufacturing of Options:
  A) producer gas
  B) natural gas
  C) synthetic gas
  D) industrial gas
  Show Answer
  The correct answer is C .
• Question 102: What is the pH of 0.001 mol dm^-3 solution of sodium hydroxide Options:
  A) 14
  B) 13
  C) 12
  D) 11
  Show Answer
  The correct answer is D .
• Question 103: When ΔH is negative, a reaction is said to be Options:
  A) endothermic
  B) exothermic
  C) reversible
  D) ionic
  Show Answer
  The correct answer is B .
• Question 104: The three-dimensional shape of methane is Options:
  A) hexagonal
  B) trigonal
  C) linear
  D) tetrahedral
  E) cubical
  Show Answer
  The correct answer is D .
• Question 105:

  A binary compound of oxygen with another element is referred to as?

  Options:
  A) Oxide
  B) Element
  C) Carbon
  D) Nitrogen
  Show Answer
  The correct answer is A .
• Question 106:

  What is the PH of 0.00 1 moldm${}^3$ solution of the sodium hydroxide

  Options:
  A) 14
  B) 13
  C) 12
  D) 11
  Show Answer
  The correct answer is D .
• Question 107: The correct order of increasing boiling points of the following compounds C₃H₇OH, C₇H₁₆ and C₄H₁₀ is Options:
  A) C₃H₇OH → C₄H₁₀ → C₇H₁₀
  B) C₄H₁₀ → C₇H₁₆ → C₃H₇OH
  C) C₇H₁₆ → C₃H₇OH → C₄H₁₀
  D) C₄H₁₀ → C₃H₇OH → C₇H₁₆
  Show Answer
  The correct answer is D .
• Question 108: Copper is displaced from the solution of its salts by most metals because it Options:
  A) is a transition element
  B) is at the bottom of the activity series
  C) is very reactive
  D) has completely filled 3d-orbitals
  Show Answer
  The correct answer is B .
• Question 109:

  Which of the following sets of operation will completely separate a mixture of sodium chloride, sand and iodine?

  Options:
  A) addition of water, filtration, evaporation to dryness and sublimation
  B) filtration, evaporation to dryness, addition of water and sublimation
  C) sublimation, filtration, evaporation and addition of water
  D) sublimation, addition of water, filtration and evaporation to dryness
  Show Answer
  The correct answer is A .
• Question 110: A substance Z reacts with NaOH to give salt and water only. When Z is treated with dilute HCl, a gas is evolved which gives a yellow suspension on passing into concentrated H₂SO₄. Substance Z is? Options:
  A) NaHS
  B) Na₂SO₃
  C) Na₂S
  D) NaHSO₃
  Show Answer
  The correct answer is A .