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 801:

  

  Use the following option above to answer this question. Which of the following compounds in solution will turn red litmus paper blue?

  Options:
  A) A
  B) B
  C) C
  D) D
  Show Answer
  The correct answer is C .
• Question 802: Chromatography is used to separate components of mixtures which differ in their rates of? Options:
  A) diffusion
  B) migration
  C) reaction
  D) sedimentaion
  Show Answer
  The correct answer is B .
• Question 803:

  What happens to the position of equilibrium, if a reversible exothermic reaction is subjected to a decrease in temperature?

  Options:
  A) The position of equilibrium shifts to the left
  B) The position of equilibrium shifts to the right.
  C) The position of equilibrium remains unchanged
  D) The reaction stops
  Show Answer
  The correct answer is B .
• Question 804:

  Zn _(s) + CuSO ₄(aq) → ZnSO ₄(aq) + Cu _(s)

  In the reaction above, the oxidation number of the reducing agent changes from

  Options:
  A) 0 to + 4
  B) 0 to + 2
  C) + 1 to + 2
  D) + 1 to + 3
  Show Answer
  The correct answer is B .
• Question 805:

  What is the concentration of a solution containing 2g of NaOH in 100cm³ of solution?

  [Na=23, O=16, H=1]

  Options:
  A) 0.05 moldm^-3
  B) 0.30 moldm^-3
  C) 0.50 moldm^-3
  D) 0.40 moldm^-3
  Show Answer
  The correct answer is C .
• Question 806:

  The same current is passed for the same time through solutions of AgNO₃ and CuSO₄ connected in series. How much silver will be deposited if 1.0 g of copper is produced?

  [Cu = 63.5, S = 32, O = 16, Ag = 108, N = 14]

  Options:
  A) 1.7 g
  B) 3.4 g
  C) 6. 8 g
  D) 13. 6 g
  Show Answer
  The correct answer is B .
• Question 807:

  How many alkoxyalkanes can be obtained from the molecular formula C${}_4$H${}_{10}$O?

  Options:
  A) 4
  B) 2
  C) 1
  D) 3
  Show Answer
  The correct answer is D .
• Question 808:

  2Na ₂ O _2(s) + 2H ₂ O ₂₍₁₎ → 4 NaOH_(s) +O_2(s)

  The substance that is oxidized in the reaction above is

  Options:
  A) 2NaO_2(s)
  B) NaOH(aq)
  C) H₂O₍₁₎
  D) O_2(g)
  Show Answer
  The correct answer is A .
• Question 809: Which of the following properties is not peculiar to matter? Options:
  A) Kinetic energy of particles increases from solid to gas
  B) Random motion of particles increases from gas to solid
  C) Orderliness of particles increases from gas to liquid
  D) Random motion of particles increases from liquid to gas
  Show Answer
  The correct answer is B .
• Question 810:

  

  Select the right answer from the structure above.Which of the following compounds represents the polymerization product of ethyne?

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