Chapter 16, Problem 8PE

(a)

Interpretation Introduction

Interpretation:

Direction of shift of equilibrium with changes brought in below equation has to be determined.

  $2{\text{SO}}_{\text{3}}\left(g\right)+197\text{ kJ}\rightleftharpoons {\text{2SO}}_2\left(g\right)+{\text{O}}_2\left(g\right)$

Concept Introduction:

Le Chatelier’s principle states that changes at equilibrium in system respond to reduce the changes and bring back the system to restore its equilibrium under new conditions. This principle follows certain conditions that are as follows:

1 With increase in concentration of reactants the reaction moves towards forward direction thus this increases the concentration of products. Whereas with increase in concentration of product reaction shifts towards reverse direction. This increases the concentration of reactants.

2 Change in volume affects rate of reaction only for the gaseous molecules. With increase in volume pressure decreases and equilibrium shifts towards left side to favor reactants. Whereas decrease in volume shifts equilibrium towards that side that has less number of moles of gaseous atoms to reduce the effect.

3 With increase in temperature reaction rate rises due to rise in kinetic energy. In case of endothermic reaction that is when energy is absorbed then the reaction moves in forward direction. In case of exothermic reaction that is when energy is released then reaction moves in backward direction.

4 Catalyst is a substance that affects rate of chemical reaction and thus there is no effect of it in equilibrium of reaction.

(b)

Interpretation Introduction

Interpretation:

Direction of shift of equilibrium with changes brought in below equation has to be determined.

  ${\text{4NH}}_3\left(g\right)+{\text{3O}}_2\left(g\right)\rightleftharpoons {\text{2N}}_2\left(g\right)+{\text{6H}}_{\text{2}}\text{O}\left(g\right)+1531\text{ kJ}$

Concept Introduction:

Refer to part (a).

(c)

Interpretation Introduction

Interpretation:

Direction of shift of equilibrium with changes brought in below equation has to be determined.

  ${\text{OF}}_{\text{2}}\left(g\right)+{\text{H}}_{\text{2}}\text{O}\left(g\right)\rightleftharpoons {\text{O}}_2\left(g\right)+2\text{HF}\left(g\right)+318\text{ kJ}$

Concept Introduction:

Refer to part (a).