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 11: Bronze is an alloy of Options:
  A) copper, zinc and nickel
  B) aluminium and copper
  C) copper and zinc
  D) tin and zinc
  E) tin and copper
  Show Answer
  The correct answer is E .
• Question 12: Which of the following methods may be used to prepare trioxonitrate (V) acid (nitric acid) in the laboratory? Options:
  A) Heating ammonia gas with tetraoxosulphate (VI) acid
  B) Heating ammonium trioxonitrate (V) with tetraoxosulphate (VI) acid
  C) Heating sodium trioxonitrate (V) with tetraoxosulphate (VI) acid
  D) Heating potassium trioxonitrate (V) with calcium hydroxide
  E) Heating a mixture of ammonia gas and oxygen.
  Show Answer
  The correct answer is C .
• Question 13: The efficiency of petrol as a fuel in high-compression internal combustion engines improves with an increase in the amount of? Options:
  A) branched chain alkanes
  B) straight chain alkanes
  C) cycloalkanes
  D) halogenated hydrocarbons
  Show Answer
  The correct answer is A .
• Question 14: Which of the following is formed when maltose reacts with concentrated tetraoxosulphate (VI) acid ? Options:
  A) Carbon (IV) oxide
  B) Coal tar
  C) Charcoal
  D) Toxic fumes
  Show Answer
  The correct answer is C .
• Question 15: The general formula of alkanones is Options:
  A) RCHO
  B) R₂CO
  C) RCOOH
  D) RCOOR
  Show Answer
  The correct answer is B .
• Question 16:

  Which of the following separation techniques can be employed in obtaining solvent from its solution?

  Options:
  A) Evaporation
  B) Distillation
  C) Filtration
  D) Precipitation
  Show Answer
  The correct answer is B .
• Question 17: The fuming of kettles is caused by the presence in the water of Options:
  A) Calcium tetraoxosulphate (VI)
  B) Calcium hydrogentrioxocarbonate (IV)
  C) Calcium hydroxide
  D) Calcium trioxocarbonate (IV)
  Show Answer
  The correct answer is B .
• Question 18: A metal that can be extracted from cassitertite is Options:
  A) cacium
  B) magnesium
  C) tin
  D) copper
  Show Answer
  The correct answer is C .
• Question 19: Metalliods are also referred to as Options:
  A) semi-metals
  B) metals
  C) colliods
  D) non-metals
  Show Answer
  The correct answer is A .
• Question 20: The air around smelting industries is likely to contain Options:
  A) H₂S, CO and N₂
  B) CO₂, SO₃ and H₂
  C) H₂, SO₂ and CO₂
  D) SO₂, N₂ and CO₂
  Show Answer
  The correct answer is C .