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 461: Which of the following gases has a characteristic pungent smell, turns red litmus paper blue and forms dense white fumes with hydrogen chloride gas? Options:
  A) N₂
  B) N₂O
  C) CI₂
  D) NH₃
  Show Answer
  The correct answer is D .
• Question 462: The IUPAC nomenclature of compound CH₃CH₂COOCH₂CH₃ is Options:
  A) propyl ethanoate
  B) ethyl butanoate
  C) ethyl propanoate
  D) methyl butanoate
  Show Answer
  The correct answer is C .
• Question 463:

  

  In the electrolysis of aqueous solution of K₂SO ₄ in the above cell, which species migrate to the anode?

  Options:
  A) SO^2-OH ^-
  B) K ⁺ and SO ₄^2-
  C) OH and HO
  D) H₃O ⁺ and K
  Show Answer
  The correct answer is A .
• Question 464:

  Oxygen is absent in?

  Options:
  A) Kerosene
  B) Soil
  C) Glass
  D) Cement
  Show Answer
  The correct answer is A .
• Question 465: Which of the following compounds is NOT formed by the action of chlorine on methane? Options:
  A) CH₃CI
  B) C₂H₅CI
  C) CH₂CI₂
  D) CHCI₃
  Show Answer
  The correct answer is B .
• Question 466: At 25^oC and 1atm, a gas occupies a volume of 1.50dm³. What volume will it occupy at 100^oC and 1atm? Options:
  A) 1.88 dm³
  B) 6.00 dm³
  C) 18.80 dm³
  D) 18.80 dm³
  E) 60.00dm³
  Show Answer
  The correct answer is A .
• Question 467:

  What is the principal ore of iron, from which iron is extracted?

  Options:
  A) Calcite
  B) Bauxite
  C) Magnetite
  D) Hematite
  Show Answer
  The correct answer is D .
• Question 468:

  2H_2(g) + O_2(g) → 2H₂ O_(g)

  In the reaction above, what volume of hydrogen would be left over when 300 cm³ of oxygen and 1000 cm³ of hydrogen are exploded in a sealed tube?

  Options:
  A) 200 cm³
  B) 400 cm³
  C) 600 cm³
  D) 700 cm³
  Show Answer
  The correct answer is B .
• Question 469:

  For the general equation of the nature

  XP + yQ ⇌ mR + nS, the expression for the equilibrium constant is

  Options:
  A) k[P]${}^x$[Q]${}^y$
  B) $\frac{m[R][S]}{x[P]y[Q]}$
  C) $\frac{[P{]}^x[Q{]}^y}{[R{]}^m[S{]}^n}$
  D) $\frac{[R{]}^m[S{]}^n}{[P{]}^x[Q{]}^y}$
  Show Answer
  The correct answer is D .
• Question 470:

  Alkanes are used mainly?

  Options:
  A) in the textile industry
  B) in the hydrogenation of oils
  C) as domestic and industrial fuels
  D) as fine chemicals
  Show Answer
  The correct answer is C .