Question

How do to measure the solubility of a solid?

Answer 1

The solubility of a compound can be measured using the solubility product constant, or `K_(sp)`.

Explanation:

The following equation shows the dissolution of `AgCl` in water.

`AgCl_((s))->Ag_((aq))^++Cl_((aq))^-`

The solubility product expression can be written like this:

`K_(sp)=[Ag^+][Cl^-]`

The solid `AgCl` is not included, because solids are not included in equilibrium expressions.

The `K_(sp)` value for `AgCl` is about `1.77*10^-10`:

`K_(sp)=[Ag^+][Cl^-]=1.77*10^-10`

This means that if the concentration of `Ag^+` and `Cl^-` ions in a solution exceed `1.77*10^-10` when multiplied together, solid `AgCl` will precipitate out of the solution.