Q. 9.32 - An Introduction to General, Organic, and Biological Chemistry

Question

Predict whether each of the following ionic compounds is soluble in water:

a. $AgCl$

b. $KI$

c. $N{a}_{2}S$

d. $A{g}_{2}O$

e. $CaS{O}_4$

Step-by-Step Solution

Answer

(part a) The ionic compound $AgCl$ is insoluble in water.

(part b) The ionic compound $KI$ is soluble in water.

(part c) The ionic compound $N{a}_{2}S$ is soluble in water.

(part d) The ionic compound $A{g}_{2}O$ is insoluble in water.

(part e) The ionic compound $CaS{O}_4$ is insoluble in water.

Step1: Introduction (part a).

Ionic compounds are those that are constituted by ionic species connecting together via electrostatic forces.

Step2: Find the ionic compound is soluble in water or not (part a).

Given:

$AgCl$

$A{g}^{+}$ and $C{l}^{-}$ ions are present in the ionic compound $AgCl$. Silver compounds do not dissolve in the water. Therefore, $AgCl$ is insoluble in water.

Step3: Find the ionic compound is soluble in water or not (part b).

Given:

$Kl$

$K^{+}$ and $I^{-}$ ions are present in the ionic compound $KI.$ In water, $K^{+}$ ions have always been soluble. As a result, $Kl$ is soluble in water.

Step4: Find the ionic compound is soluble in water or not (part c).

Given:

$N{a}_{2}S$

The ionic compound $N{a}_{2}S$ contains $N{a}^{+}$ and $S^{-2}$ ions. Usually sulfides are insoluble in water but $N{a}^{+}$ions are always soluble in water. For this reason, $N{a}_{2}S$ is soluble in water.

Step5: Find the ionic compound is soluble in water or not (part d).

Given:

$A{g}_{2}O$

Like most metal oxides and silver compounds, the ionic compound $A{g}_{2}O$ is insoluble in water.

Step6: Find the ionic compound is soluble in water or not (part e).

Given:

$CaS{O}_4$

$C{a}^{+2}$ and $S{O_4}^{-2}$ions are present in the ionic compound $CaS{O}_4$ Therefore, $CaS{O}_4$is insoluble in water.