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 2291: Which of the following statements is correct during the electrolysis of a caustic soda solution using platinum electrodes? Options:
  A) Oxygen gas is given off at the cathode
  B) Hydrogen gas is given of at the anode
  C) Sodium metals is deposited at the anode
  D) Sodium metal is deposited at the cathode
  E) AAlkalinity at the cathode increases
  Show Answer
  The correct answer is E .
• Question 2292: The oxide that remains unchanged when heated in hydrogen is? Options:
  A) CuO
  B) Fe₂O₃
  C) PbO₂
  D) ZnO
  Show Answer
  The correct answer is B .
• Question 2293: The reaction between ammonia and ethyl ethanoate produces Options:
  A) propanol and ethanamide
  B) propanol and propanamide
  C) ethanol and propanamide
  D) ethanol and ethanamide
  Show Answer
  The correct answer is D .
• Question 2294: Alkanals can be distinguished from alkanones by the reaction with Options:
  A) sudan lll stain
  B) starch iodide paper
  C) lithium tetrahydrido aluminate (lll)
  D) fehling's solution
  Show Answer
  The correct answer is D .
• Question 2295: The property used in the industrial preparation of nitrogen and oxygen from air is Options:
  A) rate of diffusion
  B) density
  C) boiling point
  D) solubility
  Show Answer
  The correct answer is C .
• Question 2296: Which of the following CANNOT be obtained by fractional distillation of petroleum? Options:
  A) Ether
  B) Methane
  C) Butane
  D) Ethene
  E) Hydrogen
  Show Answer
  The correct answer is E .
• Question 2297:

  

  Use the figure above to answer this question. Which of the following is NOT a monomer?

  Options:
  A) A
  B) B
  C) C
  D) D
  Show Answer
  The correct answer is A .
• Question 2298: Which of the following happens during the electrolysis of molten sodium chloride? Options:
  A) Sodium ion loses an electron
  B) Chlorine atom gains an electron
  C) Chlorine ion gains an electron
  D) Sodium ion is oxidized
  E) Chloride ion is oxidized
  Show Answer
  The correct answer is E .
• Question 2299: Water can be obtained as the only product during the Options:
  A) combustion of hydrocarbons
  B) neutraliization of an acid by base
  C) combustion of hydrogen
  D) electrolysis of brine
  Show Answer
  The correct answer is C .
• Question 2300: The weakest attractive force that can be observed between two molecules is Options:
  A) ionic
  B) covalent
  C) co-ordinate covalent
  D) vander Waals
  Show Answer
  The correct answer is D .