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: What is the decrease in volume of air when pyrogallol is shaken with 30.00cm³ of air ? Options:
  A) 15.00cm³
  B) 6.30cm³
  C) 0.63cm³
  D) 0.06cm³
  Show Answer
  The correct answer is B .
• Question 102: A compound commonly used for sterilization and preservation of specimens and food is Options:
  A) ethanol
  B) benzene
  C) ether
  D) ammonia
  Show Answer
  The correct answer is A .
• Question 103: Which of the following represents the balanced equation for the reaction of copper with concentrated trioxonitrate (V) acid? Options:
  A) Cu _(s) + 2HNO _3(aq) → Cu (NO ₃) _2(aq) + H _2(g)
  B) Cu _(s) + 4HNO _3(aq) → Cu (NO ₃) _2(aq) + 2H ₂O ₍₁₎ + 2NO _2(g)
  C) 3Cu _(s) + 8HNO_3(aq) → 3Cu (NO₃)_2(aq) + 4H₂O₍₁₎ + 2NO_(g)
  D) 3Cu_(s) + 4HNO_3(aq) → 3Cu(NO ₃) _2(aq) + 2H ₂O ₍₁₎ + 2NO _(g)
  Show Answer
  The correct answer is B .
• Question 104:

  The molecular shape and bond angle of water are respectively

  Options:
  A) linear, 180°
  B) bent, 109.5°
  C) tetrahedral, 109.5°
  D) bent, 105°
  Show Answer
  The correct answer is D .
• Question 105:

  How many grams of H₂SO₄ are necessary for the preparation of 0.175 dm³ of M 6.00 M H₂SO₄?

  (S = 32.06, O = 16.00 H = 1.00)

  Options:
  A) 206.0 g
  B) 103.0 g
  C) 98.1 g
  D) 51.5 g
  Show Answer
  The correct answer is B .
• Question 106:

  A substance that is used as a ripening agent for fruits is

  Options:
  A) ethene
  B) propane
  C) methane
  D) butane
  Show Answer
  The correct answer is A .
• Question 107:

  A dense white fume is formed when ammonia gas reacts with

  Options:
  A) O_2(g)
  B) H_2(g)
  C) Cl_2(g)
  D) HCl_(g)
  Show Answer
  The correct answer is D .
• Question 108: Which of the activities is commonly used as a nuclear fuel Options:
  A) uranium
  B) palladium
  C) actium
  D) thorium
  Show Answer
  The correct answer is A .
• Question 109: A piece of burning sulphur will continue to burn in a gas jar of oxygen to give misty fumes which readily dissolved in water. The resulting liquid is Options:
  A) sulphur (VI) trioxide
  B) tetraoxosulphate (VI) acid
  C) trioxosulphate (IV) acid
  D) dioxosulphate (II) acid
  E) hydrogen sulphide
  Show Answer
  The correct answer is C .
• Question 110: Liquid X, reacts with sodium trioxocarbonate (IV) (Na₂CO₃) to give a gas which turns calcium chloride solution milky X is Options:
  A) Na₂SO₄(aq)
  B) Kl (aq)
  C) an alkali
  D) an acid
  E) a hydrocarbon
  Show Answer
  The correct answer is D .