Chapter 16, Problem 34E

Interpretation Introduction

(a)

Interpretation:

The direction of the equilibrium on increasing concentration of ${\text{NH}}_4^{+}$ is to be stated.

Concept introduction:

Equilibrium is the state where the concentration of the reactant is equal to the concentration of the product. According to Le Chatelier’s Principle, it states that the equilibrium shifts in such a way or a direction that it can reduce the effect of change.

Answer to Problem 34E

On increasing the concentration of ${\text{NH}}_4^{+}$, equilibrium shifts to the left.

Explanation of Solution

The given reaction is shown below.

${\text{NH}}_{\text{4}}\text{OH}\left(aq\right)\rightleftarrows {\text{NH}}_4^{+}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)$

On increasing the concentration of ${\text{NH}}_4^{+}$, the equilibrium shifts to the left. According to Le Chatelier’s principle, the equilibrium alters its direction in order to counteract the change. Therefore, on increasing the concentration of ${\text{NH}}_4^{+}$, the equilibrium shifts to the left to decrease the concentration of ${\text{NH}}_4^{+}$.

Conclusion

The effect of increasing concentration of ${\text{NH}}_4^{+}$ has been stated above.

Interpretation Introduction

(b)

Interpretation:

The effect of decreasing concentration of hydroxide ion is to be stated.

Concept introduction:

Equilibrium is the state where the concentration of the reactant is equal to the concentration of the product. According to Le Chatelier’s Principle, it states that the equilibrium shifts in such a way or a direction that it can reduce the effect of change.

Answer to Problem 34E

The equilibrium shifts to the right on decreasing concentration of hydroxide ion.

Explanation of Solution

The given reaction is shown below.

${\text{NH}}_{\text{4}}\text{OH}\left(aq\right)\rightleftarrows {\text{NH}}_4^{+}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)$

On decreasing the concentration of ${\text{OH}}^{-}$, the equilibrium shifts to the right. According to Le Chatelier’s principle, the equilibrium alters its direction in order to counteract the change. Therefore, on decreasing the concentration of ${\text{OH}}^{-}$, the equilibrium shifts to the right to increase the concentration of ${\text{OH}}^{-}$.

Conclusion

The effect of decreasing concentration of ${\text{OH}}^{-}$ has been stated above.

Interpretation Introduction

(c)

Interpretation:

The direction of the equilibrium on increasing concentration of ${\text{NH}}_{\text{4}}\text{OH}$ is to be stated.

Concept introduction:

Equilibrium is the state where the concentration of the reactant is equal to the concentration of the product. According to Le Chatelier’s Principle, it states that the equilibrium shifts in such a way or a direction that it can reduce the effect of change.

Answer to Problem 34E

On increasing the concentration of ${\text{NH}}_{\text{4}}\text{OH}$, equilibrium shifts to the right.

Explanation of Solution

The given reaction is shown below.

${\text{NH}}_{\text{4}}\text{OH}\left(aq\right)\rightleftarrows {\text{NH}}_4^{+}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)$

On increasing the concentration of ${\text{NH}}_{\text{4}}\text{OH}$, the equilibrium shifts to the right. As according to Le Chatelier’s principle, the equilibrium alters its direction in order to counteract the change. Therefore, on increasing the concentration of ${\text{NH}}_{\text{4}}\text{OH}$, the equilibrium shifts to the right to decrease the concentration of ${\text{NH}}_{\text{4}}\text{OH}$.

Conclusion

The effect of increasing concentration of ${\text{NH}}_{\text{4}}\text{OH}$ has been stated above.

Interpretation Introduction

(d)

Interpretation:

The direction of the equilibrium on decreasing $\text{pH}$ is to be stated.

Concept introduction:

Equilibrium is the state where the concentration of the reactant is equal to the concentration of the product. According to Le Chatelier’s Principle, it states that the equilibrium shifts in such a way or a direction that it can reduce the effect of change.

Answer to Problem 34E

On decreasing $\text{pH}$, equilibrium shifts to the right.

Explanation of Solution

The given reaction is shown below.

${\text{NH}}_{\text{4}}\text{OH}\left(aq\right)\rightleftarrows {\text{NH}}_4^{+}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)$

On decreasing the $\text{pH}$, more hydrogen ions are produced. Increased hydrogen ion concentration would increase the neutralization reaction between hydrogen and hydroxide ions. Therefore, there will be a decrease in concentration of hydroxide ion concentration and the equilibrium will shift towards the right.

Conclusion

The direction of the equilibrium on decreasing $\text{pH}$ has been stated above.

Interpretation Introduction

(e)

Interpretation:

The direction of the equilibrium on adding solid $\text{KCl}$ is to be stated.

Concept introduction:

Equilibrium is the state where the concentration of the reactant is equal to the concentration of the product. According to Le Chatelier’s Principle, it states that the equilibrium shifts in such a way or a direction that it can reduce the effect of change.

Answer to Problem 34E

On adding solid $\text{KCl}$, there is no effect on equilibrium.

Explanation of Solution

The given reaction is shown below.

${\text{NH}}_{\text{4}}\text{OH}\left(aq\right)\rightleftarrows {\text{NH}}_4^{+}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)$

On adding solid $\text{KCl}$, there is no effect on the equilibrium as the ions produced by $\text{KCl}$ will not alter the contents of reaction mixture.

Conclusion

The effect of adding solid $\text{KCl}$ has been stated above.

Interpretation Introduction

(f)

Interpretation:

The direction of the equilibrium on adding gaseous ${\text{NH}}_{\text{3}}$ is to be stated.

Concept introduction:

Equilibrium is the state where the concentration of the reactant is equal to the concentration of the product. According to Le Chatelier’s Principle, it states that the equilibrium shifts in such a way or a direction that it can reduce the effect of change.

Answer to Problem 34E

On adding gaseous ${\text{NH}}_{\text{3}}$, the equilibrium shift towards the left.

Explanation of Solution

The given reaction is shown below.

${\text{NH}}_{\text{4}}\text{OH}\left(aq\right)\rightleftarrows {\text{NH}}_4^{+}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)$

On adding gaseous ammonia, more of ammonium hydroxide ions are produced. Therefore, the equilibrium shifts to the left to decrease the concentrations of hydroxide ions.

Conclusion

The effect of adding gaseous ${\text{NH}}_{\text{3}}$ has been stated above.

Interpretation Introduction

(g)

Interpretation:

The direction of the equilibrium on adding solid $\text{KOH}$ is to be stated.

Concept introduction:

Equilibrium is the state where the concentration of the reactant is equal to the concentration of the product. According to Le Chatelier’s Principle, it states that the equilibrium shifts in such a way or a direction that it can reduce the effect of change.

Answer to Problem 34E

On adding solid $\text{KOH}$ equilibrium shifts to the left.

Explanation of Solution

The given reaction is shown below.

${\text{NH}}_{\text{4}}\text{OH}\left(aq\right)\rightleftarrows {\text{NH}}_4^{+}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)$

On adding solid $\text{KOH}$, the concentration of hydroxide ion increase and therefore the equilibrium shifts to the left to decrease the concentration of hydroxide ions.

Conclusion

The effect of adding solid $\text{KOH}$ has been stated above.

Interpretation Introduction

(h)

Interpretation:

The direction of the equilibrium on adding solid ${\text{NH}}_{\text{4}}\text{Cl}$ is to be stated.

Concept introduction:

Equilibrium is the state where the concentration of the reactant is equal to the concentration of the product. According to Le Chatelier’s Principle, it states that the equilibrium shifts in such a way or a direction that it can reduce the effect of change.

Answer to Problem 34E

On adding solid ${\text{NH}}_{\text{4}}\text{Cl}$, equilibrium shifts to the right.

Explanation of Solution

The given reaction is shown below.

${\text{NH}}_{\text{4}}\text{OH}\left(aq\right)\rightleftarrows {\text{NH}}_4^{+}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)$

On adding solid ${\text{NH}}_{\text{4}}\text{Cl}$, the equilibrium shifts towards the right as the concentration of ammonium ion increases.

Conclusion

The effect of adding solid ${\text{NH}}_{\text{4}}\text{Cl}$ on equilibrium has been stated.