Waec Chemistry 2018 Past Questions and Answers

Question 11:

• WAEC 2018

Consider the following reaction equation: \(Br_{2} + 2KI \to 2KBr + I_{2}\). Bromine is acting as

A. An oxidizing agent
B. A reducing agent
C. An acid
D. A base

Question 12:

• WAEC 2018

Ethene is produced from ethanol by

A. Decomposition
B. Hydrolysis
C. Ozonolysis
D. Dehydration

Question 13:

• WAEC 2018

Consider the following equilibrium reaction: \(2AB_{{2}{(g)}} + B_{{2}{(g)}} \to 2AB_{{3}{(g)}}\). \(\Delta H= -X kJmol^{-1}\). The backward reaction will be favored by

A. A decrease in pressure
B. An increase in pressure
C. A decrease in temperature
D. An introduction of a positive catalyst

Question 14:

• WAEC 2018

What is the mass of solute in 500\(cm^{3}\) of 0.005\(moldm^{-3}\) \(H_{2}SO_{4}\)? ( H = 1, S = 32.0, O=16.0)

A. 0.490g
B. 0.049g
C. 0.245g
D. 0.0245g

Question 15:

• WAEC 2018

Pure water can be made to boil at a temperature lower than 100°C by

A. Reducing its quantity
B. Decreasing the external pressure
C. Distilling it
D. Increasing the external pressure