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 1981: Smoke consist of? Options:
  A) solid particles dispersed in liquid
  B) solid or liquid particles dispersed in gas
  C) gas or liquid particles dispersed inliquid
  D) liquid particles dispersed inliquid
  Show Answer
  The correct answer is B .
• Question 1982: When iron is exposed to moisture and it rusts, the value of ΔG for the reaction is Options:
  A) neutral
  B) zero
  C) positive
  D) negative
  Show Answer
  The correct answer is D .
• Question 1983: The reaction of an alkanol with an alkanoic acid in the presence of concentrated H₂SO₄ will produce an? Options:
  A) alkanal
  B) alkanoate
  C) alkanone
  D) alkyne
  Show Answer
  The correct answer is B .
• Question 1984: Which of the following contains two amphoteric oxides? Options:
  A) sodium oxide, Zinc oxide , Magnesium oxide
  B) Aluminium oxide, Calcium oxide, Zinc oxide
  C) Potassium oxide, Lithium oxide, Carbon monoxide
  D) Silver oxide, Lead oxide, Sodium oxide
  E) Sulphur dioxide, Aluminium oxide, Carbon monoxide
  Show Answer
  The correct answer is B .
• Question 1985: A solution of calcium bromide contains 20 g dm ³ What is the molarity of the solution with respect to calcium bromide and bromide ions? [Ca = 40, Br = 80] Options:
  A) 0. 1, 0 . 1
  B) 0. 1, 0. 2
  C) 0. 1, 0. 05
  D) 0.05, 0.1
  Show Answer
  The correct answer is C .
• Question 1986: MnO^-₄ + 8H⁺ + ne → Mn⁺⁺ + 4H₂O. Which is the value of n in the reaction above? Options:
  A) 2
  B) 3
  C) 4
  D) 5
  Show Answer
  The correct answer is D .
• Question 1987: The carbon atoms on ethane are Options:
  A) sp² hybridized
  B) sp³ hybridized
  C) sp⁴ hybridized
  D) sp hybridized
  Show Answer
  The correct answer is B .
• Question 1988: Which of the following gases contains the highest number of atoms at s.t.p? Options:
  A) 6 moles of neon
  B) 3 moles of oxygen
  C) 2 moles of chlorine
  D) 1 mole of ethane
  Show Answer
  The correct answer is A .
• Question 1989: The process involved in the conversion of an oil into margarine is known as? Options:
  A) hydrogenation
  B) condensation
  C) pyrolysis
  D) dehydration
  E) cracking
  Show Answer
  The correct answer is A .
• Question 1990: Which of the following atoms represents deuterium? Options:
  A) No protons = 1, No of neutrons = 0, No of electrons = 0
  B) No protons = 1, No of neutrons = 0, No of electrons = 1
  C) No protons = 1, No of neutrons = 1, No of electrons = 1
  D) No protons = 1, No of neutrons = 2, No of electrons = 1
  Show Answer
  The correct answer is C .