Chapter U6.5, Problem 3E

(a)

Interpretation Introduction

Interpretation: For the given reversible reaction, equilibrium equation needs to be written.

Concept introduction: For a reversible reaction, equilibrium is a state when both reactants and products have equal concentrations and it does not change with time.

An equilibrium reaction is represented as follows:

  $A+B\rightleftharpoons AB$

At equilibrium, the change in the concentration of A, B is same as change in concentration of AB. For example, if concentration of A and B decreases by x value, the concentration of AB will increase by x .

Explanation of Solution

The given reaction is represented as follows:

  ${\text{H}}_2\left(g\right)+{\text{Cl}}_2\left(g\right)\rightleftharpoons 2\text{HCl}\left(g\right)$

The equilibrium equation can be represented for the above reaction as follows:

  $K=\frac{{\left[\text{HCl}\left(g\right)\right]}^2}{\left[{\text{H}}_2\left(g\right)\right]\left[{\text{Cl}}_2\left(g\right)\right]}$

Here, $\left[\text{HCl}\left(g\right)\right]$ , $\left[{\text{H}}_2\left(g\right)\right]$ and $\left[{\text{Cl}}_2\left(g\right)\right]$ is equilibrium concentration of hydrochloride gas, hydrogen gas and chlorine gas respectively.

(b)

Interpretation Introduction

Interpretation: Whether there is more product or reactant in the equilibrium mixture needs to be determined.

Concept introduction: An equilibrium reaction is represented as follows:

  $A+B\rightleftharpoons AB$

For the above reaction, the change in concentration of A and B is equal to that of AB.

For the above reaction, equilibrium constant can be represented as follows:

  $K=\frac{\left[AB\right]}{\left[A\right]\left[B\right]}$

Here, K is equilibrium constant.

Explanation of Solution

If the value of equilibrium constant K is more than 1 then product is favored in the reaction but, if the value of K is less than 1 then reactant is favored in the reaction.

Thus, if the value of K for an equilibrium reaction is known, it can be determine whether it is product or reactant favored.

The given value of equilibrium constant is $4.05\times {10}^{31}$ .

The above value of K is more than 1, even is very large value thus, products will be favored in the equilibrium reaction. Therefore, there will be more products in the equilibrium mixture.