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 1121:

  How many bonding pair are present in carbon(iv)oxide?

  Options:
  A) 4
  B) 3
  C) 2
  D) 1
  Show Answer
  The correct answer is A .
• Question 1122: How many isomeric forms are there for the molecular formula C₃H₆Br₂? Options:
  A) 1
  B) 2
  C) 3
  D) 4
  E) 5
  Show Answer
  The correct answer is D .
• Question 1123: Which of the following is not an alkali? Options:
  A) Ca(OH)₂
  B) NH₃
  C) NaOH
  D) Al(OH)₃
  Show Answer
  The correct answer is B .
• Question 1124: The product of the electrolysis of dilute sodium hydroxide using platinum electrodes are Options:
  A) Hydrogen and oxygen gases
  B) Water and hydrogen gas
  C) Water and sodium metal
  D) Sodium metal and oxygen gas
  Show Answer
  The correct answer is A .
• Question 1125: The correct order of increasing oxidation number of the transition metal ions for the compounds K₂Cr₂O₇, V₂O₅ and KMnO₄ is Options:
  A) V₂O₅< K_2Cr2O₇< KMnO₄
  B) K₂Cr₂O₇< KMnO_{4 < V2O5}
  C) KMnO₄< K_2Cr2O₇< V_2O5
  D) KMnO₄< V_2O5< K_2Cr2O₇
  Show Answer
  The correct answer is A .
• Question 1126: Which of the following sulphides is insoluble in dilute HCl? Options:
  A) Na₂S
  B) ZnS
  C) CuS
  D) FeS
  Show Answer
  The correct answer is C .
• Question 1127: The ores that can be concentrated by flotation are Options:
  A) nitride ores
  B) sulphide ores
  C) oxide ores
  D) non-metals
  Show Answer
  The correct answer is B .
• Question 1128:

  An organic compound X has the following properties:
  I. It is not miscible with water.
  ll. It has boiling point of 77^oC.
  lll. It has a sweet odour.
  IV. lt is insoluble in sodium hydrogen carbonate solution.
  V lt does not decolourize bromine water.
  X is therefore

  Options:
  A) methane
  B) ethanoic acid
  C) ethene
  D) ethyl ethanoate
  E) carbon tetrachloride
  Show Answer
  The correct answer is D .
• Question 1129: Cathode rays cause an object placed behind a perforated anode to cast a shadow on the screen. This observation shows that the rays Options:
  A) are positively charged
  B) are negatively charged
  C) Have mass
  D) travel in straight lines
  Show Answer
  The correct answer is D .
• Question 1130: Hydrogen is readily released when dilute hydrochloric acid reacts with Options:
  A) Cu
  B) Na
  C) Au
  D) Ag
  Show Answer
  The correct answer is B .