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 311: Which of the following is NOT a true statement of the kinetic Theory of Gases? Options:
  A) The molecules move at random
  B) The size of molecules is negligble as compared with the volume of gas
  C) The molecular collisions are perfectly elastic
  D) Every molecule has the same kinetic energy at a particular temperature
  E) The average kinetic energy is proportional to the absolute temperature of the gas
  Show Answer
  The correct answer is D .
• Question 312: What will happen if an aluminium spoon is used to stir a solution of iron (II) trioxonitrates (V)? Options:
  A) The spoon will be oxidized while the iron (II) ions will be reduced to the metal
  B) The spoon will increase in size
  C) The spoon will be reduced while the iron (II) ions will be oxidized
  D) The spoon will be reduced
  Show Answer
  The correct answer is A .
• Question 313: When air is compressed? Options:
  A) its density decreases
  B) it solidifies
  C) its temperature decreases
  D) its temperature increases
  E) its temperature remains unchanged
  Show Answer
  The correct answer is C .
• Question 314:

  The elements in the periodic table are listed in order of increasing

  Options:
  A) relative atomic number
  B) atomic mass
  C) relative isotopic mass
  D) nuclear charge
  Show Answer
  The correct answer is B .
• Question 315: Iron galvanized with zinc is cathodically protected from corrosion. This is because? Options:
  A) zinc has a more positive oxidation potential than iron
  B) zinc has less positive oxidation potential than iron
  C) bith have the same oxidation potential
  D) zinc is harder than iron
  Show Answer
  The correct answer is B .
• Question 316: Which of the following represents the balanced equation for the reaction of copper with concentrated trioxonitrate (V) acid? Options:
  A) Cu _(s) + 2HNO _3(aq) → Cu (NO ₃) _2(aq) + H _2(g)
  B) Cu _(s) + 4HNO _3(aq) → Cu (NO ₃) _2(aq) + 2H ₂O ₍₁₎ + 2NO _2(g)
  C) 3Cu _(s) + 8HNO_3(aq) → 3Cu (NO₃)_2(aq) + 4H₂O₍₁₎ + 2NO_(g)
  D) 3Cu_(s) + 4HNO_3(aq) → 3Cu(NO ₃) _2(aq) + 2H ₂O ₍₁₎ + 2NO _(g)
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  The correct answer is B .
• Question 317: The chemicals used to soften hard water involves the addition of Options:
  A) insoluble sodium compounds which from soluble solutions of calcium and magesium
  B) solube soudium compounds which from soluble solutions of calcium and magnesium ions
  C) solube sodium compounds which from insoluble precipitates of calcium and magnesium ions
  D) insoluble precipitates of calcium and magnesium ions
  Show Answer
  The correct answer is C .
• Question 318:

  

  In the diagram above, X is the

  Options:
  A) Enthalphy
  B) Activated complex
  C) Activation energy
  D) Enthalphy change
  Show Answer
  The correct answer is D .
• Question 319: The product obtained when a mixture of benzene vapour and hydrogen are passed over nickel catalyst at 180^oC is Options:
  A) cyclohexane
  B) cyclopentane
  C) n- hexane
  D) n - pentane
  Show Answer
  The correct answer is A .
• Question 320: The metal that liberates hydrogen from cold water in bubbles only is Options:
  A) Na
  B) K
  C) Ca
  D) Al
  Show Answer
  The correct answer is C .