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 1821:

  Using the metal activity series, the metal that can liberate hydrogen gas from steam is?

  Options:
  A) iron
  B) copper
  C) tin
  D) lead
  Show Answer
  The correct answer is A .
• Question 1822: When air is passed through alkaline pyrogallol and then over quicklime, the only gases left are? Options:
  A) nitrogen and carbondoxide
  B) the rare gases
  C) nitrogen and oxygen
  D) nitrogen and the rare gases
  E) nitrogen, carbonioxide and the rare gases
  Show Answer
  The correct answer is D .
• Question 1823: CH₃CH₂Cl + KCN → CH₃CH₂CN + KClIn the reaction above, the cyanide is Options:
  A) hydrophobic
  B) hydrophilic
  C) nucleophilic
  D) electrophilic
  Show Answer
  The correct answer is C .
• Question 1824:

  Which of the following gases contains the least number of atoms at s.t.p?

  Options:
  A) 1 mole of butane
  B) 4 moles of chlorine
  C) 3 moles of ozone
  D) 7 moles of argon
  Show Answer
  The correct answer is A .
• Question 1825:

  RS_(aq) + HF_(aq) → RF_(s) + HS_(aq)

  ΔH = -65.7 kj mol^(-1).

  From the equation above, it can be deduced that

  Options:
  A) the heat content of the reactants is lower than that of the products
  B) the heat content of the reactants is higher than that of the products
  C) the reaction is slow
  D) a large amount of heat is absorbed
  Show Answer
  The correct answer is B .
• Question 1826: The isomers of C₃H₈O ARE Options:
  A) 1 - propanol and 2 - propanol
  B) 1 - propanol and 1 - propanol
  C) 2 - propanol and 2 - propanone
  D) 2 - propanol and 1 - propanol
  Show Answer
  The correct answer is A .
• Question 1827: Which of the following pairs has compounds that are isomers? Options:
  A) Propanal and propanone
  B) Ethanoic acid and ethylmethanoate
  C) Ethanoic acid and ethane-1, 2-diol
  D) 2-methylbutane and 2, 2-dimethylbutane
  Show Answer
  The correct answer is D .
• Question 1828:

  Which of the following gases contains the least number of atoms at s.t.p?

  Options:
  A) 1 mole of butane
  B) 4 moles of chlorine
  C) 3 moles of ozone
  D) 7 moles of argon
  Show Answer
  The correct answer is A .
• Question 1829:

  Isotopes of an element have

  Options:
  A) The same number of protons but different numbers of neutrons.
  B) The same number of neutrons and electrons
  C) The same number of protons and neutrons
  D) The same number of protons and electrons
  Show Answer
  The correct answer is A .
• Question 1830: The postulate of Dalton's atomic theory which still holds is that Options:
  A) atoms can neither be created nor destroyed
  B) the particles of the same element are exactly alike
  C) particles of different elements combine in simple whole number ratio
  D) all elemets are made of small indivisible particles
  Show Answer
  The correct answer is A .