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 1361:

  

  From the diagram above the mass of crystals deposited when 1 dm ³ of a saturated solution of NaCl is cooled from 80^oC to 60^oC is

  [Na = 23, Cl = 35.5]

  Options:
  A) 117.00 g
  B) 58.50 g
  C) 11.70 g
  D) 5.85 g
  Show Answer
  The correct answer is A .
• Question 1362: How many moles of HCl will be required to react with potassium heptaoxodichromate (VI) to produce 3 moles of chlorine? Options:
  A) 14
  B) 12
  C) 11
  D) 10
  Show Answer
  The correct answer is A .
• Question 1363: The pollutants that are likely to be present in an industrial environment are? Options:
  A) H₂S,SO₂ and oxides of nitrogen
  B) NH₃, HCI and CO
  C) CO₂, NH₃ and H₂S
  D) dust, NO and CI₂
  Show Answer
  The correct answer is A .
• Question 1364: A form of carbon used for absorbing poisonous gases and purification of noble gases is Options:
  A) wood charcoal
  B) animal charcoal
  C) carbon fibres
  D) carbon black
  Show Answer
  The correct answer is A .
• Question 1365:

  The sub-atomic particles located in the nucleus of an atomare?

  Options:
  A) neutron and proton
  B) proton and electron
  C) proton and ions
  D) neutron and electron
  Show Answer
  The correct answer is A .
• Question 1366: A compound commonly used for sterilization and preservation of specimens and food is Options:
  A) ethanol
  B) benzene
  C) ether
  D) ammonia
  Show Answer
  The correct answer is A .
• Question 1367: Reduction of alkanonoes with LialH₄ produces Options:
  A) primary alkanols
  B) secondary alkanols
  C) tertiary alkanols
  D) polyhydric alkanols
  Show Answer
  The correct answer is B .
• Question 1368:

  2SO${}_2$ ${}_{(g)}$+ O${}_2$ ${}_{(g)}$ ↔ 2SO${}_3$${}_{(g)}$ ΔH = -395.7kJmol${}^{-1}$

  In the equation, an increase in temperature will shift the equilibrium position to the

  Options:
  A) left and equilibrium constant decreases
  B) left and equilibrium constant increases
  C) right and equilibrium constant increases
  D) right and equilibrium constant decreases
  Show Answer
  The correct answer is A .
• Question 1369:

  At room temperature and standard pressure, chlorine gas is in which state of matter?

  Options:
  A) Plasma
  B) Solid
  C) Liquid
  D) Gas
  Show Answer
  The correct answer is D .
• Question 1370:

  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 .