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 2131: H ₂O _(g) + C _(s) → H_2(g) + CO_(g)The oxidizing agent in the reaction above is Options:
  A) CO_(g)
  B) C_(s)
  C) H₂O_(g)
  D) H_(2)(g)
  Show Answer
  The correct answer is C .
• Question 2132: Sulphur (IV) oxide bleaches by Options:
  A) Reduction
  B) Oxidation
  C) Hydration
  D) Adsorption
  Show Answer
  The correct answer is A .
• Question 2133: The carbon atoms on ethane are Options:
  A) sp² hybridized
  B) sp³ hybridized
  C) sp⁴ hybridized
  D) sp hybridized
  Show Answer
  The correct answer is B .
• Question 2134:

  The densities of two gases, X and Y, are 0.5 g dm^-3 and 2.0 dm^-3 respectively.

  What is the rate of diffusion of X relative to Y?

  Options:
  A) 0.1
  B) 0.5
  C) 2.0
  D) 4.0
  Show Answer
  The correct answer is C .
• Question 2135: Which of the following salts will turn blue litmus red? Options:
  A) Sodium tetrahydroxozincate (ll)
  B) Potassium hydrogentetraoxosulphate (lV)
  C) Sodium trioxocarbonate (lV)
  D) Zinc chloride hydroxide
  Show Answer
  The correct answer is B .
• Question 2136: Which of the following statements is NOT true of electrovalent compounds? Options:
  A) They are solids
  B) They do not vaporized easily
  C) They usually dissolve in water
  D) The elements forming the compounds normally have their valency electrons in a shared state
  E) They conduct electricity
  Show Answer
  The correct answer is D .
• Question 2137:

  Chlorine gas is commonly used in the production of which of the following industrial compounds?

  Options:
  A) Chlorofluorocarbons (CFCs)
  B) Methane
  C) Ammonia
  D) Ethanol
  Show Answer
  The correct answer is A .
• Question 2138: which of the following polymers is suitable for packaging and electrical insulation? Options:
  A) polyamide
  B) polyethene
  C) polycarbonate
  D) polystyrene
  Show Answer
  The correct answer is D .
• Question 2139: Mortar is NOT used for under-water construction because Options:
  A) it hardens by lose of water
  B) its hardening doe not depend upon evaporation
  C) it requires concrete to harden
  D) it will be washed away by the flow of water
  Show Answer
  The correct answer is A .
• Question 2140:

  

  It can be deduced from the vapour pressure curves above that

  Options:
  A) liqiud 1 has the highest boiling point
  B) liquid ll has the highest boiling point
  C) liquid lll has the highest boiling point
  D) liquid lll has the lowest boiling point
  Show Answer
  The correct answer is C .