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 1461: Which of the following is physical change? Options:
  A) Burning kerosene
  B) Freezing ice cream
  C) Exposing white phosphorus
  D) Dissolving calcium in water
  Show Answer
  The correct answer is B .
• Question 1462: 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 1463: The postulate of Dalton's atomic theory which still holds is that Options:
  A) atoms can neither be created nor destroyed
  B) the particles of the same element are exactly alike
  C) particles of different elements combine in simple whole number ratio
  D) all elemets are made of small indivisible particles
  Show Answer
  The correct answer is A .
• Question 1464: The raw materials used for the smelting of iron ore in a furnace is Options:
  A) CaSO₄
  B) CaCO₃
  C) CuSO₄
  D) Zn(NO₃)₂
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  The correct answer is B .
• Question 1465: A certain volume of gas at 298k is heated such that its volume and pressure are now four times the original values. What is the new temperature? Options:
  A) 18.6k
  B) 100.0k
  C) 298.0k
  D) 1192.0k
  E) 4768.0k
  Show Answer
  The correct answer is E .
• Question 1466:

  How many moles of limestone will be required to produce 5.6g of CaO?

  [Ca = 40, C = 12, O= 16]

  Options:
  A) 0.20 mol
  B) 0.10 mol
  C) 1.12 mol
  D) 0.56 mol
  Show Answer
  The correct answer is B .
• Question 1467: Incomplete oxidation of ethanol yields Options:
  A) CH₃COOH
  B) CH₃COCH₃
  C) CH₃CH₂OCH₂CH₃
  D) CH₂CHO
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  The correct answer is D .
• Question 1468: The function of conc. H₂SO₄ in the esterification of ethanoic acid with ethanol is to Options:
  A) serve as a dehydrating agent
  B) serve as a solvent
  C) act as a catalyst
  D) prevent any side reaction
  E) serve as an oxidizing agent
  Show Answer
  The correct answer is C .
• Question 1469:

  In the preparation of salts, the method employed will depend on the?

  Options:
  A) composition
  B) dissociating ability
  C) stability to heat
  D) precipitating ability
  Show Answer
  The correct answer is C .
• Question 1470:

  

  The IUPAC nomenclature of the compound above is

  Options:
  A) 2-ethylpentane
  B) 3,4-dimethylhexane
  C) 2,3-dimethylhexane
  D) 2-ethylhexane
  Show Answer
  The correct answer is B .