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:

  A sample of any of the following substances disappearsafter some time when exposed to air like camphor, naphthalene, or dry ice. This phenomenon is called?

  Options:
  A) Sublimation
  B) Evaporation
  C) Diffusion
  D) Radiation
  Show Answer
  The correct answer is A .
• Question 2: Which of the following statements is true of sulphur (IV) oxide? Options:
  A) It forms tetraoxosulphate (VI) acid with water
  B) It is an odourless gas
  C) It is an acid hybride
  D) It forms white precipitate with acidified barium chloride
  Show Answer
  The correct answer is C .
• Question 3:

  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 4:

  Neutrons were discovered by?

  Options:
  A) James Chadwick
  B) Ernest Rutherford
  C) J.J Thompson
  D) John Dalton
  Show Answer
  The correct answer is A .
• Question 5:

  An organic compound with fishy smell is likely to have a general formula?

  Options:
  A) RCONHR${}^1$
  B) RCONH${}_2$
  C) RNH${}_2$
  D) RCOR${}^1$
  Show Answer
  The correct answer is C .
• Question 6: The chemical reaction which takes place at the anode (positive electrode) in electrolysis is? Options:
  A) oxidation
  B) hydrolysis
  C) dissociation
  D) reduction
  E) disproportionation
  Show Answer
  The correct answer is A .
• Question 7: A jet plane carrying 3,000 kg of ethane burns off all the gas forming water and carbondioxide. if all the carbondioxide is expelled and all the water formed is condensed and kept on board the plane, then the gain in weight is Options:
  A) 1,800 kg
  B) 900 kg
  C) 600 kg
  D) 2, 400 kg
  E) 1, 200 kg
  Show Answer
  The correct answer is D .
• Question 8: Which of the following types of alkanols undergo oxidation to produce alkanoic acids? 1. Primary alkanols 11. Secondary alkanols 111. Tertiary alkanols Options:
  A) 1,11 and 111
  B) l and ll only
  C) ll only
  D) l only
  Show Answer
  The correct answer is D .
• Question 9: The raw materials used for the smelting of iron ore in a furnace is Options:
  A) CaSO₄
  B) CaCO₃
  C) CuSO₄
  D) Zn(NO₃)₂
  Show Answer
  The correct answer is B .
• Question 10:

  

  Use the option above to answer this question. The graph that describes a zero order reaction is

  Options:
  A) A
  B) B
  C) C
  D) D
  Show Answer
  The correct answer is B .