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 1: The mass number of an atom is? Options:
  A) the number of electrons in the atom
  B) the number of protons in the nucleus of the atom
  C) the number of neutrons in the nucleus of the atom
  D) the sum of numbers of electrons and protons inthe atom
  E) the sum of numbers of proton and neutrons in the nucleus of the atom
  Show Answer
  The correct answer is E .
• Question 2:

  Identify the reducing agent in the following reaction:
  Zn + CuSO${}_4$ ZnSO${}_4$ + Cu

  Options:
  A) Cu
  B) Zn
  C) ZnSO${}_4$
  D) CuSO${}_4$
  Show Answer
  The correct answer is B .
• Question 3: The product formed when propanol is heated over a copper catalyst in the absence of oxygen are Options:
  A) CH₃CH₂CHO and H₂
  B) CH₃CHO and CO₂
  C) CH₃CH₂COOH and H₂
  D) CH₃COOH and CO₂
  Show Answer
  The correct answer is D .
• Question 4:

  Which functional group is present in alkanals?

  Options:
  A) Carbonyl group (C=O)
  B) Hydroxyl group (-OH)
  C) Alkyl group (-R)
  D) Carboxyl group (-COOH)
  Show Answer
  The correct answer is A .
• Question 5:

  Calculate the pH of 0.05 moldm${}^{-3}$ H${}_2$SO${}_4$

  Options:
  A) 1.30
  B) 1.12
  C) 1.00
  D) 0.30
  Show Answer
  The correct answer is A .
• Question 6: Ca(OH)_2(s) + 2NH₄Cl_(g) → CaCl_2(s) + 2H₂O_2(l) + X. In the reaction above X is Options:
  A) NO₂
  B) NH₃
  C) N₂O
  D) NO₂
  Show Answer
  The correct answer is B .
• Question 7:

  If the volume of a given mass of a gas at 0ºc is29.5cm${}^3$. What will be the volume of the gas at 15ºc, given that the pressure remains constant.

  Options:
  A) 31.6
  B) 62.2
  C) 32.7
  D) 31.1
  Show Answer
  The correct answer is D .
• Question 8: All these are electromagnetic waves except Options:
  A) White light
  B) Photon
  C) X-ray
  D) Infrared
  Show Answer
  The correct answer is B .
• Question 9: 2- methylbutan- 2ol is an example of a Options:
  A) dihydric alkanol
  B) tertiary alkanol
  C) secondary alkanol
  D) primary alkanol
  Show Answer
  The correct answer is B .
• Question 10:

  Addition of charcoal to the filter bed of sand during water treatment for township supply is to?

  Options:
  A) prevent goiter
  B) prevent tooth decay
  C) remove odour
  D) kill germs
  Show Answer
  The correct answer is C .