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 61: 50 cm³ of sulphur (IV) oxide, 800 cm³ of ammonia, 450 cm³ of hydrogen chloride, 1.0 cm³ of at 15°C. Which of the following is suitable for demonstrating the fountain experiment? Options:
  A) Sulphur (IV) oxide hydrogen chloride
  B) Carbon (IV) oxide and amonia
  C) Amonia and hydrogen chloride
  D) Carbon (IV) oxide and surphur (IV) oxide
  Show Answer
  The correct answer is C .
• Question 62: Iron galvanized with zinc is cathodically protected from corrosion. This is because? Options:
  A) zinc has a more positive oxidation potential than iron
  B) zinc has less positive oxidation potential than iron
  C) bith have the same oxidation potential
  D) zinc is harder than iron
  Show Answer
  The correct answer is B .
• Question 63: Which quantum number divides shells into orbitals? Options:
  A) principal
  B) Arzimuthal
  C) Magnetic
  D) Spin
  Show Answer
  The correct answer is B .
• Question 64:

  What is the concentration of a solution containing 2g of NaOH in 100cm3 of solution? [Na = 23, O =16, H = 1]

  Options:
  A) 0.40 moldm${}^{-3}$
  B) 0.50 moldm${}^{-3}$
  C) 0.05 moldm${}^{-3}$
  D) 0.30 moldm${}^{-3}$
  Show Answer
  The correct answer is B .
• Question 65:

  The ionic radii of metals are usually

  Options:
  A) greater than their atomic radii
  B) unaffected by the charge on the ion
  C) the same as their atomic radii
  D) less than their atomic radii
  Show Answer
  The correct answer is D .
• Question 66:

  Which of the following is an example of a primary cell?

  Options:
  A) Alkaline battery
  B) Nickel-cadmium battery
  C) Lead-acid battery
  D) Lithium-ion battery
  Show Answer
  The correct answer is A .
• Question 67: Water can be obtained as the only product during Options:
  A) combustion of hydrocarbons
  B) neutralization of an acid by base
  C) combustion of hydrogen
  D) electrolysis of brine
  E) boiling water
  Show Answer
  The correct answer is C .
• Question 68:

  Addition of charcoal to the filter bed of sand during water treatment for township supply is to?

  Options:
  A) prevent goiter
  B) prevent tooth decay
  C) remove odour
  D) kill germs
  Show Answer
  The correct answer is C .
• Question 69: 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 70: A few drops of concentrated HNO₃ is added to an unknown solution and boiled for a while. If this produces a brown solution, the cation presents is likely to be Options:
  A) Pb²⁺
  B) Cu²⁺
  C) Fe³⁺
  D) Fe²⁺
  Show Answer
  The correct answer is D .