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 181: A trihydric alkanol is Options:
  A) Glycerol
  B) Phenol
  C) Glycol
  D) Ethanol
  Show Answer
  The correct answer is A .
• Question 182: 3.0g of a mixture of potassium carbonate and potassium chloride were dissolved in a 25cm³ of this solution required required 40.00cm₃ of 0.1M HCl for neutralization. What is the percentage by weight of K₂CO₃ in the mixture. (K = 39, O = 16, C = 12) Options:
  A) 60
  B) 72
  C) 82
  D) 89
  E) 92
  Show Answer
  The correct answer is E .
• Question 183: Alkanones are generally obtained by the oxidation of Options:
  A) primary alkanols
  B) secondary alkanols
  C) tertiary alkanols
  D) alkanoic acid
  Show Answer
  The correct answer is B .
• Question 184: The boiling of fat and aqueous caustic soda is referred to as Options:
  A) hydrolysis
  B) esterification
  C) acidification
  D) saponification
  Show Answer
  The correct answer is D .
• Question 185:

  A chemical widely used as a fertilizer is?

  Options:
  A) galena
  B) bauxite
  C) emerald
  D) nitrochalk
  Show Answer
  The correct answer is D .
• Question 186:

  An example of a polysaccharide is?

  Options:
  A) Dextrose
  B) Mannose
  C) Glucose
  D) Starch
  Show Answer
  The correct answer is D .
• Question 187: An example of aliphatic unsaturated hydrocarbon is Options:
  A) pentane
  B) butanol
  C) propene
  D) benzene
  Show Answer
  The correct answer is C .
• Question 188:

  An element, X, forms a volatile hydride XH₃ with a vapour density of 17.0. The relative atomic mass of X is?

  (H = 1)

  Options:
  A) 34.0
  B) 31.0
  C) 20.0
  D) 14.0
  Show Answer
  The correct answer is B .
• Question 189: During the electrolysis of a salt of a metal M, a current of 0.5 A flows from for 32 minutes 10 seconds and deposits 0.325 g of M, What is the charge of the metal ion?(M = 65, If = 96,500 C per mole of electron) Options:
  A) 1
  B) 2
  C) 3
  D) 4
  Show Answer
  The correct answer is B .
• Question 190: In the course of purifying water for town supply the water is passed through large settlings tanks, containing sodium aluminate (III) to remove Options:
  A) large particles
  B) germs
  C) fine particles
  D) odour
  Show Answer
  The correct answer is A .