WAEC Chemistry Past Questions & Answers - Page 203

1,011.

A reaction is represented by the equation below. A2(g) + B2(g) 2AB(g); ∆H = +X kJmol-1 Which of the following statements about the system is correct?

A.

The reaction goes to completion at equilibrium

B.

The forward reaction is exthermic

C.

At equilibrium increase in temperature favours the reverse reaction

D.

Pressure has no effect on the equilibrium mixture

Correct answer is D

No explanation has been provided for this answer.

1,012.

Consider the following equation: Ag+ (aq) + CI-(aq) → Ag+CI- (s) ; ∆H = _65.7 kJmol-1. From the equation, it can be deduced that

A.

direct combination is involved and the reaction is endothermic

B.

a solid is formed and heat is evolved

C.

activation energy is high and a catalyst is required

D.

the reaction is endothermic and occurs at high temperature

Correct answer is B

No explanation has been provided for this answer.

1,013.

What does ∆H represent in the following equation ? Cl(g) + e- → CI- (g); ∆H = - 363 kJ mol-1

A.

lonization energy

B.

Electron affinity

C.

Dissociation energy

D.

Heat of atomization

Correct answer is B

No explanation has been provided for this answer.

1,014.

It can be concluded that gastric juice

A.

contains enzymes

B.

is acidic

C.

is a mixture

D.

has pH value of 7

Correct answer is B

No explanation has been provided for this answer.

1,015.

A gas was evolved when a sample of gastric juice reacted with sodium trioxocarbonate (IV) . The gas evolved was

A.

NH3

B.

SO2

C.

HCI

D.

CO2

Correct answer is D

No explanation has been provided for this answer.