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 1021:

  A quantity of electricity liberates 3.6g of Silver from its salt. What mass of aluminium Will be liberated from its salt by the same quantity of electricity? [Al = 27, Ag = 108].

  Options:
  A) 2.7g
  B) 1.2g
  C) 0.9g
  D) 0.3g
  Show Answer
  The correct answer is A .
• Question 1022: What mass of sodium carbonate solution is in 500 cm³ of 0.1 molar sodium carbonate solution?(Na = 23, C = 12, O = 16) Options:
  A) 10.6 g
  B) 5.3 g
  C) 500 g
  D) 10 g
  E) 20 g
  Show Answer
  The correct answer is B .
• Question 1023: When ethanol is heated with excess concentrated sulphuric acid, the ethanol is? Options:
  A) oxidized to ethene
  B) polymerized to polyethene
  C) dehydrated to ethene
  D) dehydrated to ethyne
  Show Answer
  The correct answer is C .
• Question 1024:

  Which of the following best represent solid gas mixture?

  Options:
  A) milk
  B) kerosene
  C) soil
  D) smoke
  Show Answer
  The correct answer is D .
• Question 1025: Which of the following compounds is NOT formed by the action of chlorine on methane? Options:
  A) CH₃CI
  B) C₂H₅CI
  C) CH₂CI₂
  D) CHCI₃
  Show Answer
  The correct answer is B .
• Question 1026:

  In a reaction: SnO + 2C → Sn + 2CO, the mass of coke containing 80% carbon required to reduce 0.302 kg of pure tin oxide is?

  (Sn - 119, O - 16, C - 12).

  Options:
  A) 0.40 kg
  B) 0.20 kg
  C) 0.06 kg
  D) 0.04 kg
  Show Answer
  The correct answer is C .
• Question 1027: The saponification of an alkanoate to produce soap and alkanol involves Options:
  A) dehydration
  B) esterification
  C) hydrolysis
  D) oxidation
  Show Answer
  The correct answer is C .
• Question 1028:

  Which of the following describes the chemical property of acids?

  Options:
  A) None of the above
  B) Acid + XCO${}_3$ $\to$ Salt + H${}_2$O + NH${}_3$
  C) Acid + NaOH $\to$ Normal salt + CO${}_2$
  D) Acid + X${}_n$CO${}_3$ $\to$ Salt + H${}_2$O + CO${}_2$
  Show Answer
  The correct answer is D .
• Question 1029:

  When ammonia and hydrogen ion bond together to form ammonium ion, the bond formed is called

  Options:
  A) electrovalent bond
  B) co-ordinate bond
  C) ionic bond
  D) covalent bond
  Show Answer
  The correct answer is B .
• Question 1030:

  

  Use the diagram to answer this question.

  The gas that can be used to demonstrate the experiment is

  Options:
  A) hydrogen chloride
  B) hydrogen sulphide
  C) nitrogen(ll) oxide
  D) dinitrogen (l) oxide
  Show Answer
  The correct answer is A .