Waec Chemistry 2019 Past Questions and Answers

Question 26:

• WAEC 2019

which of the following pairs of substances has the highest heat of neutralization?

A. Strong acid and strong base
B. Weak acid and weak base
C. Strong acid and weak base
D. Weak acid and strong base

Question 27:

• WAEC 2019

When quicklime dissolves in water?

A. Heat is absorbed
B. Heat is evolved
C. Oxygen is liberated
D. Hydrogen is given off

Question 28:

• WAEC 2019

If the value of ΔH is positive for a reaction, it means that the reaction is?

A. Exothermic
B. Endothermic
C. Spontaneous
D. Slow

Question 29:

• WAEC 2019

Which of the following compounds is formed by the oxidation of ethanol?

A. C\(_2\)H\(_4\)CO\(_2\)H
B. C\(_2\)H\(_5\)CO\(_2\)H
C. CH\(_3\)OH
D. CH\(_3\)CO\(_2\)H

Question 30:

• WAEC 2019

What is the name of the gas liberated when diluted hydrochloric acid is added to iron(ii)sulphide?

A. Turns lime water milky
B. Decolorizes bromine water
C. Gives a pop sound
D. Turns lead(ii)ethanoate paper black