Chapter 16, Problem 39E

Interpretation Introduction

(a)

Interpretation:

The direction of the equilibrium on increasing concentration of calcium 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 39E

On increasing the concentration of calcium, equilibrium shifts to the left.

Explanation of Solution

The given reaction is shown below.

${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2\left(s\right)\rightleftarrows 3{\text{Ca}}^{2+}\left(aq\right)+2{\text{PO}}_4^{3-}\left(aq\right)$

On increasing the concentration of calcium, the equilibrium shifts to the left. As according to Le Chatelier’s principle, the equilibrium alters its direction in order to counteract the change. Therefore, on increasing the concentration of calcium, the equilibrium shifts to the left to decrease the concentration of calcium.

Conclusion

The effect of increasing concentration of calcium has been stated above.

Interpretation Introduction

(b)

Interpretation:

The direction of the equilibrium on increasing concentration of phosphate 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 39E

The equilibrium shifts to the left on increasing concentration of phosphate ion.

Explanation of Solution

The given reaction is shown below.

${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2\left(s\right)\rightleftarrows 3{\text{Ca}}^{2+}\left(aq\right)+2{\text{PO}}_4^{3-}\left(aq\right)$

On increasing the concentration of phosphate, the equilibrium shifts to the left. As according to Le Chatelier’s principle, the equilibrium alters its direction in order to counteract the change. Therefore, on increasing the concentration of phosphate, the equilibrium shifts to the left to decrease the concentration of phosphate.

Conclusion

The effect of increasing concentration of phosphate has been stated above.

Interpretation Introduction

(c)

Interpretation:

The direction of the equilibrium on decreasing concentration of calcium 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 39E

On decreasing the concentration of calcium the equilibrium shifts to the right.

Explanation of Solution

The given reaction is shown below.

${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2\left(s\right)\rightleftarrows 3{\text{Ca}}^{2+}\left(aq\right)+2{\text{PO}}_4^{3-}\left(aq\right)$

On decreasing the concentration of calcium, 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 decreasing the concentration of calcium, the equilibrium shifts to the right to increase the concentration of calcium.

Conclusion

The effect of decreasing concentration of calcium has been stated above.

Interpretation Introduction

(d)

Interpretation:

The direction of the equilibrium on decreasing concentration of phosphate 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 39E

On decreasing the concentration of phosphate, equilibrium shifts to the right

Explanation of Solution

The given reaction is shown below.

${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2\left(s\right)\rightleftarrows 3{\text{Ca}}^{2+}\left(aq\right)+2{\text{PO}}_4^{3-}\left(aq\right)$

On decreasing the concentration of phosphate, 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 decreasing the concentration of phosphate, the equilibrium shifts to the right to increase the concentration of phosphate.

Conclusion

The effect of decreasing concentration of phosphate has been stated above.

Interpretation Introduction

(e)

Interpretation:

The direction of the equilibrium on adding solid ${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2$ 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 39E

On adding solid ${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2$, equilibrium shifts to the right.

Explanation of Solution

The given reaction is shown below.

${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2\left(s\right)\rightleftarrows 3{\text{Ca}}^{2+}\left(aq\right)+2{\text{PO}}_4^{3-}\left(aq\right)$

On adding solid ${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2$, the concentration of calcium phosphate increases in the reaction mixture. Therefore, according to Le Chatelier’s principle, the equilibrium shifts to the right to decrease the concentration of ${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2$.

Conclusion

The effect of adding solid ${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2$ has been stated above.

Interpretation Introduction

(f)

Interpretation:

The direction of the equilibrium on adding solid ${\text{Ca}}_3{\left({\text{NO}}_3\right)}_2$ 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 39E

On adding solid ${\text{Ca}}_3{\left({\text{NO}}_3\right)}_2$, equilibrium shifts to the left.

Explanation of Solution

The given reaction is shown below.

${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2\left(s\right)\rightleftarrows 3{\text{Ca}}^{2+}\left(aq\right)+2{\text{PO}}_4^{3-}\left(aq\right)$

On adding solid ${\text{Ca}}_3{\left({\text{NO}}_3\right)}_2$, the calcium ion concentration increases in the reaction mixture. Therefore, to overcome this increasing concentration of calcium ion, the equilibrium shifts to the left.

Conclusion

The effect of adding solid ${\text{Ca}}_3{\left({\text{NO}}_3\right)}_2$ has been stated above.

Interpretation Introduction

(g)

Interpretation:

The direction of the equilibrium on adding solid ${\text{KNO}}_3$ 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 39E

Solid ${\text{KNO}}_3$ has no effect on the equilibrium.

Explanation of Solution

The given reaction is shown below.

${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2\left(s\right)\rightleftarrows 3{\text{Ca}}^{2+}\left(aq\right)+2{\text{PO}}_4^{3-}\left(aq\right)$

On adding solid ${\text{KNO}}_3$, there is no effect on the equilibrium as no common ions are produced.

Conclusion

The effect of adding solid ${\text{KNO}}_3$ has been stated above.

Interpretation Introduction

(h)

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 39E

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

Explanation of Solution

The given reaction is shown below.

${\text{Ca}}_3{\left({\text{PO}}_4\right)}_2\left(s\right)\rightleftarrows 3{\text{Ca}}^{2+}\left(aq\right)+2{\text{PO}}_4^{3-}\left(aq\right)$

On decreasing $\text{pH}$, the concentration of hydrogen ions increases and therefore the equilibrium shifts to the right as more hydrogen ions combine with phosphate ions and decrease the concentration of phosphate ion in the reaction mixture. Therefore, the equilibrium shifts to the right.

Conclusion

The effect of decreasing $\text{pH}$ has been stated above.