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 1071: When plastics and packaging materials made from chloroethene are burnt in the open, the mixture of gases released into the atmosphere is most likely to contain? Options:
  A) ethane
  B) chlorine
  C) hydrogen chloride
  D) ethene
  Show Answer
  The correct answer is C .
• Question 1072:

  Which one of the following is not a mixture?

  Options:
  A) Air
  B) Mercury
  C) Milk
  D) Cement
  Show Answer
  The correct answer is B .
• Question 1073: In a water body, too much sewage leads to Options:
  A) a decrease in the temperature of the water which cause in death of aquatic animals
  B) an increase in the number of aquatic animals in the water
  C) an increase in the bacterial population which reduces the level of oxygen in the water
  D) a decrease in the bacterial population which increases the level of oxygen in the water
  Show Answer
  The correct answer is C .
• Question 1074: Water is poured over a white solid and a colourless neutral gas is evolved which burns with a sooty flame. The white solid is? Options:
  A) calcium
  B) calcium oxide
  C) calcium carbide
  D) sodium peroxide
  E) sodium sulphate
  Show Answer
  The correct answer is C .
• Question 1075:

  An element used in the production of matches is

  Options:
  A) nitrogen
  B) aluminium
  C) copper
  D) sulphur
  Show Answer
  The correct answer is D .
• Question 1076:

  In the reaction N₂(g) + O(g) ↔ 2NO(g) produced an increase in the total pressure will?

  Options:
  A) cause less nitrogen to be produced in the equilibrium mixture
  B) cause less nitric oxide to be produced in the equilibrium mixture
  C) cause more nitric oxide to be produced in the equilibrium mixture
  D) cause more oxygen to be produced in the equilibrium mixture
  E) have no effect
  Show Answer
  The correct answer is E .
• Question 1077: The gasification of coke is used for the manufacture of Options:
  A) producer gas
  B) natural gas
  C) synthetic gas
  D) industrial gas
  E) artificial gas
  Show Answer
  The correct answer is A .
• Question 1078:

  56.00cm³ of a gas at S.T.P. weighed 0.11g. What is the vapour density of the gas?

  [Molar volume of a gas at S.T.P = 22.4dm³]

  Options:
  A) 11.00
  B) 22.00
  C) 33.00
  D) 44.00
  Show Answer
  The correct answer is B .
• Question 1079: At the same temperature and pressure, 50 cm³ of nitrogen gas contains the same number of molecules as? Options:
  A) 25 cm³ of methane
  B) 40 cm³ of hydrogen
  C) 50 cm³ of ammonia
  D) 100 cm³ of chlorine
  Show Answer
  The correct answer is C .
• Question 1080: SO₃ is NOT directly dissolved in water in the preparation of H₂SO₄ by the contact process because? Options:
  A) the reaction between SO₃ and water is violently exothermic
  B) acid is usually added to water and never water to acid
  C) SO₃ does not dissolve in water readily
  D) SO₃ is an acid gas
  Show Answer
  The correct answer is A .