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: 2SO_2(g) + O_2(g) ↔ 2SO_3(g). In the chemical reaction above, the substance that will increase the rate of production of sulphur (VI) oxide is Options:
  A) manganese (IV) oxide
  B) finely divided iron
  C) vanadium (V) oxide
  D) nickel
  Show Answer
  The correct answer is C .
• Question 2: C₃H_8(g) + 50_2(g) → 4H₂O + 3CO_2(g). Form the equation above the volume of oxygen at s.t.p. required to burn 50cm³ of propane is? Options:
  A) 250 cm³
  B) 150 cm³
  C) 100 cm ³
  D) 50 cm³
  Show Answer
  The correct answer is A .
• Question 3: The formula CH₂ for ethanoic acid is regarded as its Options:
  A) Molecular formula
  B) General formula
  C) Empirical formula
  D) Structural formula
  Show Answer
  The correct answer is C .
• Question 4:

  What happens to the position of equilibrium, if a reversible exothermic reaction is subjected to a decrease in temperature?

  Options:
  A) The position of equilibrium shifts to the left
  B) The position of equilibrium shifts to the right.
  C) The position of equilibrium remains unchanged
  D) The reaction stops
  Show Answer
  The correct answer is B .
• Question 5: An increase in temperature causes an increase in pressure of a gas in a fixed volume due to an increase in the? Options:
  A) number of molecules of the gas
  B) density of the gas molecules
  C) number of collisions between the gas molecules
  D) number of collisions between the gas molecules and the walls of the container
  Show Answer
  The correct answer is D .
• Question 6:

  117.0g of sodium chloride was dissolved in the solubility in 1.0dm³ of distilled water at 25^oC. Determine the solubility in mol dm^-3 of sodium chloride at that temperature

  [Na = 23, Cl = 35.5]

  Options:
  A) 1.0
  B) 2.0
  C) 3.0
  D) 4.0
  Show Answer
  The correct answer is B .
• Question 7:

  CH₃-CH-CH₃

  CH₂CI Is known as?

  Options:
  A) 1-chloro-2-methylbutane
  B) 1-chloro-2-methylpropane
  C) 2-chloromethylpropane
  D) 1-chloro-2, 2-dimethylethane
  Show Answer
  The correct answer is B .
• Question 8: The forces holding naphthalene crystals together can be overcome when naphthalene is heated to a temperature of 354K resulting in the crystal to melting. These forces are known as? Options:
  A) coulombic
  B) ionic
  C) covalent
  D) Van der waals
  Show Answer
  The correct answer is D .
• Question 9:

  The following compounds are given with their corresponding boiling points.

  Compound Boiling Point

  i.................................14°C

  ii................................24°C

  iii................................0°C

  iv................................120°C

  V.................................-2°C

  From the above information, indicate which of the following is correct?

  Options:
  A) All the compounds are gaseous at 20 °C
  B) One of the compounds is gaseous at 20 °C
  C) Two of the compounds are gaseous at 20 °C
  D) Three of the compounds are gaseous at 20 °C
  E) None of the compounds is gaseous at 20 °C
  Show Answer
  The correct answer is D .
• Question 10:

  What is the PH of 0.00 1 moldm${}^3$ solution of the sodium hydroxide

  Options:
  A) 14
  B) 13
  C) 12
  D) 11
  Show Answer
  The correct answer is D .