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 1:

  Which of the following is a unique property of water compared to other liquids?

  Options:
  A) It is a poor solvent
  B) It does not evaporate
  C) It expands when freezing
  D) It has a low heat capacity
  Show Answer
  The correct answer is C .
• Question 2: Lucas reagent is used to test for Options:
  A) alkanes
  B) alkanoic acids
  C) alkanols
  D) amines
  Show Answer
  The correct answer is C .
• Question 3: Which of the following compounds is a base? Options:
  A) CO₂
  B) CaO
  C) H₃PO₃
  D) CH₃COOCH₃
  Show Answer
  The correct answer is B .
• Question 4:

  In the reaction:

  2Hl_(g) ↔ H_2(g) + l_2(g)' ΔH = 10 kj;

  The concentration of iodine in the equilibrium mixture can be increased by?

  Options:
  A) raising the pressure
  B) raising the temperature
  C) adding a catalyst
  D) lowering the pressure
  Show Answer
  The correct answer is B .
• Question 5: A gas sample with an initial volume of 3.25 dm³ is heated and allowed to expand to 9.75 dm³ at constant pressure. What is the ratio of the final absolute temperature to the initial absolute temperature? Options:
  A) 3:1
  B) 5:2
  C) 5:4
  D) 8:3
  Show Answer
  The correct answer is A .
• Question 6: In what way is equilibrium constant for the forward reaction related to that of the reversed reaction? Options:
  A) The additional of the two is expected to be one
  B) The product of the two is expected to be one
  C) The two equilibrium constants are identical
  D) The product of the two is always greater than one
  Show Answer
  The correct answer is A .
• Question 7: In the extraction of iron in the blast furnace, limestone is used to? Options:
  A) release CO₂ for the reaction
  B) reduce the iron ore
  C) increase the strenght of the iron
  D) remove impurities
  Show Answer
  The correct answer is D .
• Question 8: Which of the following compounds can be represented by the molecular formula C2 H6O? Options:
  A) propanal
  B) ethanol
  C) methanoic acid
  D) glucose
  Show Answer
  The correct answer is B .
• Question 9: To obtain pure carbon (II) oxide from its mixture with carbon (IV) oxide, the mixture should be Options:
  A) passed over heated copper (II) oxide
  B) bubbled through water
  C) bubbled through concentrated tetroxosulphate (VI) acid
  D) bubbled through sodium hydroxide
  Show Answer
  The correct answer is D .
• Question 10: A reaction takes places spontaneously if?
  Options:
  A) ∆G = O
  B) ∆S < O and ∆H > O
  C) ∆H < T ∆S
  D) ∆G > O
  Show Answer
  The correct answer is C .