Chapter 17, Problem 25A

(a)

Interpretation Introduction

Interpretation:The equilibrium expression of heterogeneous equilibrium needs to be determined.

Concept introduction: Heterogeneous equilibrium can be defined as equilibrium where the components (reactants and products) are present in different phases.

Answer to Problem 25A

The equilibrium expression is $K=\frac{{[P{F}_3]}^4}{{[F_2]}^6}$

Explanation of Solution

Equilibrium expressions used to determine the changes in concentration that happens as the reaction approaches equilibrium. Aqueous solutions and gases change their concentrations considerably during the course of reaction. On the other hand, pure liquids and solids do not change their concentration much as reaction moves towards equilibrium since they are present in large excess.

Hence pure liquids and solids are not included in equilibrium expression equation.

The reaction is: $P_4\left(s\right)+6F_2\left(g\right)\rightleftharpoons 4P{F}_3\left(g\right)$

The equilibrium expression is $K=\frac{{[P{F}_3]}^4}{{[F_2]}^6}$

(b)

Interpretation Introduction

Interpretation: The equilibrium expression of heterogeneous equilibrium needs to be determined.

Concept introduction: Heterogeneous equilibrium can be defined as equilibrium where the components (reactants and products) are present in different phases.

Answer to Problem 25A

The equilibrium expression is $K=\frac{1}{[Xe]{[F_2]}^2}$

Explanation of Solution

Equilibrium expressions used to determine the changes in concentration that happens as the reaction approaches equilibrium. Aqueous solutions and gases change their concentrations considerably during the course of reaction. On the other hand, pure liquids and solids do not change their concentration much as reaction moves towards equilibrium since they are present in large excess.

Hence pure liquids and solids are not included in equilibrium expression equation.

The reaction is: $Xe\left(g\right)+2F_2\left(g\right)\rightleftharpoons Xe{F}_4\left(s\right)$

The equilibrium expression is $K=\frac{1}{[Xe]{[F_2]}^2}$

(c)

Interpretation Introduction

Interpretation: The equilibrium expression of heterogeneous equilibrium needs to be determined.

Concept introduction: Heterogeneous equilibrium can be defined as equilibrium where the components (reactants and products) are present in different phases.

Answer to Problem 25A

The equilibrium expression is $K=\frac{[O_2]}{{[C{l}_2]}^4}$

Explanation of Solution

Equilibrium expressions used to determine the changes in concentration that happens as the reaction approaches equilibrium. Aqueous solutions and gases change their concentrations considerably during the course of reaction. On the other hand, pure liquids and solids do not change their concentration much as reaction moves towards equilibrium since they are present in large excess.

Hence pure liquids and solids are not included in equilibrium expression equation.

The reaction is: $2SiO\left(s\right)+4C{l}_2\left(g\right)\rightleftharpoons 2SiC{l}_4\left(l\right)+O_2\left(g\right)$

The equilibrium expression is $K=\frac{[O_2]}{{[C{l}_2]}^4}$