How do to measure the solubility of a solid?

1 Answer
Feb 28, 2018

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.