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 1951:

  

  The two functional groups in the above compound are

  Options:
  A) alcohol and amine
  B) acid and amine
  C) aldehyde and acid
  D) ketone and amine
  Show Answer
  The correct answer is B .
• Question 1952:

  If the heat of combustion of hydrogen is -285.8kJ,

  What is the heat of formation of water?

  Options:
  A) +571.6 kJ
  B) -571.6 kJ
  C) -285.8 kJ
  D) +285.8 kJ
  Show Answer
  The correct answer is C .
• Question 1953:

  At 25^o and zymase as catalyst,

  C₆H₁₂₆ → 2C₂H₅OH + 2CO₂ + energy

  The reaction above represented by the equation above is useful in the production of

  Options:
  A) propanol
  B) butanol
  C) methanol
  D) ethanol
  Show Answer
  The correct answer is D .
• Question 1954: Which of the following gives a precipitation when treated with NaOH Solution? Options:
  A) AlCl₃
  B) NH₄Cl
  C) Na₂CO₃
  D) CH₃COONa
  Show Answer
  The correct answer is A .
• Question 1955: Which of the following compounds is used as a gaseous fuel? Options:
  A) CH₃ -CH₂ -CHO₂ -COOH
  B) CH₃ -C = CH
  C) CH₃ -CH₂ -CH₂ -CH₃
  D) CH₂ -CH₂ -CH₃
  Show Answer
  The correct answer is C .
• Question 1956: A mixture is different from a compound because Options:
  A) the properties of a compound are those of its individual constituents while those of a mixture differ from its constituents
  B) a mixture is always homogeneous while a compound is not
  C) the constituent of a compound are chemically bound together while those of a mixture are not
  D) a mixture can be represented by a chemical formula while a compound cannot
  Show Answer
  The correct answer is C .
• Question 1957: In the electrolysis of CuSo_4(g) using platinum electrode the reaction at the anode is Options:
  A) 4H+ 4e - 2H₂
  B) 4OH^-- 4e = 2H₂O + O₂
  C) 2OH - 2e_- = 2OH
  D) 2OH^- + 2OH = 2H₂O + O₂
  Show Answer
  The correct answer is B .
• Question 1958:

  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 1959: Which of the following substances is a basic salt? Options:
  A) Na₂CO₃
  B) Mg(OH)CI
  C) NaHCO₃
  D) KSO₄.AI₂(SO₄)₃,24H₂O
  Show Answer
  The correct answer is B .
• Question 1960:

  Calculate the volume in cm³ of oxygen evolved as s.t.p. when a current of 5 A is passed through acidified water for 193s

  {F = 96500 Cmol^-1, Molar volume of a gas at s.t.p. = 22.4 dm³}

  Options:
  A) 224.000 dm³
  B) 0.056 dm³
  C) 0.224 dm³
  D) 56.000 dm³
  Show Answer
  The correct answer is B .