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 2261: Which of the following fraction is used as raw material for the cracking process? Options:
  A) kerosine
  B) lubricating oil
  C) bitumen
  D) diesel oils
  Show Answer
  The correct answer is D .
• Question 2262:

  What is the name of the process by which ammonia is produced on an industrial scale?

  Options:
  A) Nitrogenation
  B) Ammoniation
  C) Nitrification
  D) Haber process
  Show Answer
  The correct answer is D .
• Question 2263: Which of the following is used in rocket fuels? Options:
  A) HNO₃
  B) CH₃COOH
  C) H₂SO₄
  D) HCl
  Show Answer
  The correct answer is A .
• Question 2264: Which of the following physical properties decreases across the Periodic Table? Options:
  A) Ionization potenial
  B) Electron affinity
  C) Electronegativity
  D) Atomic radius
  Show Answer
  The correct answer is D .
• Question 2265: Which of the following can have an isomer? Options:
  A) C₂H₄
  B) C₄H₁₀
  C) C₃H₈
  D) C₂H₆
  E) C₆H₆
  Show Answer
  The correct answer is B .
• Question 2266: Alloys are best prepared by Options:
  A) Electroplating
  B) Arc-welding
  C) Reducing and mixture of their metallic oxide
  D) Cooling a molten mixture of the metals
  Show Answer
  The correct answer is D .
• Question 2267: 20 cm ³ of hydrogen gas are sparked with 20cm ³ of oxygen gas in an endimoeter at 373k (100 ^oC) and 1 atmosphere. The resulting mixture is cooled to 298 K (25 ^oC) and passed over calcium chloride. The volume of the residual gas is Options:
  A) 40 cm ³
  B) 20 cm ³
  C) 30 cm ³
  D) 10cm ³
  E) 5cm ³
  Show Answer
  The correct answer is D .
• Question 2268: Which of the following statement is false? Options:
  A) Acids react with some metals, liberating hydrogen
  B) Acids react with carbonates, liberating carbondioxide
  C) Acids conduct electricity and are decomposed by the current, liberating hydrogen at the anode
  D) Acids have a sour taste
  E) Acids change the colour of indicators
  Show Answer
  The correct answer is C .
• Question 2269: The principle of column chromatography is based on the ability of the constituents to Options:
  A) move at different speeds in the column
  B) dissolve in each other in the column
  C) react with the solvent in the column
  D) react with each other in the column
  Show Answer
  The correct answer is A .
• Question 2270:

  If gas A has a molar mass of 32 g/mol and gas B has a molar mass of 64 g/mol, what is the ratio of their diffusion rates?

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