Waec Chemistry 2013 Past Questions and Answers

Question 31:

• WAEC 2013

Which of the following compounds crystallizes without water of crystallization?

A. MgSO₄
B. Na₂CO₃
C. NaCI
D. FeSO₄

Question 32:

• WAEC 2013

A substance is said to be impure if

A. Its melting point range is wide
B. It dissolves in water with difficult
C. It has a low melting point
D. It is coloured

Question 33:

• WAEC 2013

The following factors affect the solubility of a solid in a given solvent except

A. Nature of solute
B. Nature of solvent
C. Pressure
D. Temperature

Question 34:

• WAEC 2013

Consider the reaction represented by the equation: N₂O_4(g) ⇌ 2NO_2(g) ; ∆H = + x kJmol^-1
What happens when the temperature is reduced at equilibrium?

A. Concentration of N ₂O_4(g) decreases
B. Concentration of N ₂O_4(g) increases.
C. Pressure exerted by the gases increases
D. Pressure exerted by the gases remains constant

Question 35:

• WAEC 2013

Which of the following cells produce electrical energy from chemical reactions?
l. Lead-acid battery ll. Dry cell III. Deniell cell IV Electrolytic cell

A. L and ll only
B. L, ll, and III only
C. Lll and IV only
D. I and III only