# What factors influence the solubility of a salt with respect to the given diagram?

Oct 6, 2016

$\text{Option 4}$ is the best candidate; i.e. (b) is the strongest electrolyte.

#### Explanation:

$\text{Option 1}$ is contraindicated. No data are conveyed with respect to solubility.

$\text{Option 2}$ is contraindicated, by the very terms of the question. Why?

$\text{Option 3}$ is again contraindicated, by the very terms of the question. Why?

And this leaves $\text{Option 4}$ as the only horse running. We started with $A {Y}_{2}$. In solution this speciated to give discrete particles of (arguably) ${A}^{2 +}$ and $2 \times {Y}^{-}$; of course the charge could have been the other way round.

In solution $\text{b}$ there was no association between cation and anion. When a strong electrolyte dissolves in water it speciates to give its constituent ions. Solutions $\text{a}$ and $\text{c}$ still showed associated ions. Why?

Real examples of $\text{Option 4}$ could include $C a C {l}_{2}$, and $N {a}_{2} S {O}_{4}$, i.e. consider the following equation representing their dissolution, are as follows:

$C a C {l}_{2} \left(s\right) \rightarrow C {a}^{2 +} + 2 C {l}^{-}$

$N {a}_{2} S {O}_{4} \left(s\right) \rightarrow 2 N {a}^{+} + S {O}_{4}^{2 -}$

This is a good and hard question designed to make you really think. I certainly had to do so!