Why is the solubility of most liquids not greatly affected by temperature?

The solubility of a solute is the maximum quantity of the
solute that will dissolve in a given quantity of solvent for a particular temperature
and pressure. A change in temperature and pressure alters the solubility of solutes
differently based on their phase.

The solubility of solids
is usually observed to increase as the temperature rises; the solubility of gases
decreases with a rise in temperature; and for liquids there is a very small
effect.

This variation for the three phases can be
explained by looking at the reason behind the change. Before solutes can dissolve, the
bonds that hold the particles together have to be broken. In the case of solids, the
bonds are quite strong and it requires a relatively large amount of energy to break the
bonds. This is facilitated by an increase in temperature. In the case of gases, the
energy with the solute particles increases with an increase in temperature that actually
reduces solubility.

In the case of liquids, the bonding
energy between particles that make up the solute is very small. A change in temperature
has very little effect on the ease with which the bonds break up. On the other hand, a
higher temperature does not significantly increase the rate at which the particles move
about. This makes the solubility of liquids vary by a very small extent with a change in
temperature.