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 1321:

  The nucleus of an atom consists of?

  Options:
  A) Electrons and neutrons
  B) Electrons and protons
  C) Protons and neutrons
  D) None of the above
  Show Answer
  The correct answer is C .
• Question 1322: Which of the following is NOT a redox reaction? Options:
  A) 2HNO₂ + 2HI → 2H₂O + 2NO + I₂
  B) Zn + H₂SO₄ → ZnSO₄ + H₂
  C) Ca(HCO₃)₂ → CaCO₃ + H₂O + CO₂
  D) 4FeO + O₂ → 2Fe₂O₃
  E) 2Na + Cl₂ → 2NaCl
  Show Answer
  The correct answer is C .
• Question 1323: 20.00 cm ³ of a solution containing 0.53 g of anhydrous Na₂CO₃ in 100 cm³ requires 25.00 cm³ of H₂SO₄ for complete neutralisation. The concentration of the acid solution in moles per dm is [H =1, C = 12, O = 16, Na =23, S = 32] Options:
  A) 0.02
  B) 0.04
  C) 0.06
  D) 0.08
  Show Answer
  The correct answer is B .
• Question 1324:

  

  Use the graph above to answer this question.If the gas is cooled, at what temperature will it start to condense?

  Options:
  A) 125 ^oC
  B) 150^oC
  C) 175^oC
  D) 250^oC
  Show Answer
  The correct answer is B .
• Question 1325:

  A basic postulate of the kinetic theory of gases is that the molecules of a gas move in straight lines between collisions. This implies that

  Options:
  A) collisions are perfectly elastic
  B) forces of repulsion exist
  C) forces of repulsion and attraction are in equilibrium
  D) collisions are inelastic
  Show Answer
  The correct answer is B .
• Question 1326:

  The process by which salt and water reacted in a limited way to form an acid or abase is?

  Options:
  A) Neutral process
  B) Basic acidic process
  C) Hydrolysis
  D) Sublimation
  Show Answer
  The correct answer is C .
• Question 1327: Hydrogen is not liberated when trioxonitrate(v)acid reacts with zinc because Options:
  A) zinx is not rendered passive by acid
  B) hydrogen produced is oxidized to water
  C) oxides of nitrogen are produced
  D) all nitrates are soluble in water
  E) trioxonitrate(v)acid is a strong acid
  Show Answer
  The correct answer is E .
• Question 1328:

  Which of the following metals is commonly alloyed with copper to make brass?

  Options:
  A) Iron
  B) Nickel
  C) Aluminum
  D) Zinc
  Show Answer
  The correct answer is D .
• Question 1329: When a little brine was added to a metal nitrate a white precipitate was formed which first turned violet and then black on exposure to ai. The metal nitrate is therefore? Options:
  A) sodium nitrate
  B) mercuric nitrate
  C) lithium nitrate
  D) silver nitrate
  E) potassium nitrate
  Show Answer
  The correct answer is D .
• Question 1330: The enzyme used in the hydrolysis of starch to dextrin and maltose is Options:
  A) Zymase
  B) Sucrase
  C) Amylase
  D) Lactase
  Show Answer
  The correct answer is C .