How does solubility change with temperature?

1 Answer

Considering 3 of the 6 general matter states...

Explanation:

Le Chatelier's Principle : "When any system at equilibrium is subjected to change in concentration, temperature, volume, or pressure, then the system readjusts itself to counteract (partially) the effect of the applied change and a new equilibrium is established" .enter link description here

I would sum it up by stating that 'equilibrum' will always struggle to be kept the same way.

Now delving into the question...

Temperature influence on solubility changes.

Solids
(Temperature is directly proportional to their Solubility [increase])

The effects differ whether the reaction is endothermic or exothermic. When it is a endothermic reaction; using Le Chatelier's principle : the system shifts toward the product side in order to alleviate this stress ...

This results in the solid being dissociated while equilibrum being re-established, when the solution temperature increases.

In contrast, it is the opposite result when talking about exothermic reactions.

Liquids

In this case, definitive predictions cannot be made. :(

Gases
(Temperature is inversely proportional to their Solubility)

Gas particles have more average kinetic energy meaning that its molecules are moving faster. Therefore, the gas particles dissolved in the liquid are more likely to escape to the gas phase, thus, less likely to be dissolved.

Increasing temperatures result in stress on the product side (where heat is). The system shifts towards the reactant side in order to ease this new stress. In consequence, the equilibrium concentration of the gas particles (in gaseous phase) increases, resulting in a lower solubility.

In contrast, it is the opposite result when decreasing the temperature.