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 51:

  

  The I.U.P.A.C name for the compound is

  Options:
  A) isopropylethene
  B) acetylene
  C) 3- methylbutane
  D) 2-methylbutane
  E) 5-methylpentane
  Show Answer
  The correct answer is D .
• Question 52:

  If one mole of aluminium contains 6 x 10²³ atoms of aluminium, how many atoms are contained in 0.9g of aluminium?

  (Al = 27)

  Options:
  A) 1.0 x 10²¹
  B) 6.6 x 10²¹
  C) 2.0 x 10²²
  D) 1.0 x 10²²
  E) 5.4 x 10²³
  Show Answer
  The correct answer is C .
• Question 53: A compound that will NOT produce oxygen on heating is? Options:
  A) potasium dioxonitrate (III)
  B) lead (IV) oxide
  C) potassium trioxochlorate (V)
  D) potassium trioxonitrate (V)
  Show Answer
  The correct answer is A .
• Question 54: A sample of orange juice is found to have a PH of 3.80. What is the concentration of the hydroxide ion in the juice? Options:
  A) 1.6 $\times$ 10^-4
  B) 6.3 $\times$ 10^-11
  C) 6.3 $\times$ 10^-4
  D) 1.6 $\times$ 10^-11
  Show Answer
  The correct answer is B .
• Question 55:

  

  In the diagram above, X is the ``

  Options:
  A) enthalpy
  B) enthalpy change
  C) activation energy
  D) activated complex
  Show Answer
  The correct answer is B .
• Question 56:

  Some copper (ll) sulphate pentahydrate (CuSO₄ 5H₂O), was heated at 120 ^oC with the following results. Wt of crucible = 10.00 g; Wt of crucible + CuSO₄ 5H₂O =14.98g; Wt of crucible + residue = 13.54 g. How many molecules of water of crystalization were lost?

  [H = 1, Cu = 63.5, O = 16, S = 32]

  Options:
  A) 1
  B) 2
  C) 3
  D) 4
  E) 5
  Show Answer
  The correct answer is D .
• Question 57: The major source of oxides of nitrogen is from the burning of Options:
  A) coal
  B) wood
  C) fuel
  D) chlrofluorocarbons
  Show Answer
  The correct answer is C .
• Question 58: Tartaric acid is used industrially to Options:
  A) make baking powder
  B) make fruit juice
  C) remove rust
  D) dry substance
  Show Answer
  The correct answer is A .
• Question 59: What current in ampere will deposit 0.27g of aluminium in 2 hours? [Al = 27, F = 96500C]. Options:
  A) 3.2
  B) 8
  C) 0.4
  D) 16
  Show Answer
  The correct answer is C .
• Question 60:

  How many alkoxyalkanes can be obtained from the molecular formula C${}_4$H${}_{10}$O?

  Options:
  A) 4
  B) 2
  C) 1
  D) 3
  Show Answer
  The correct answer is D .