Effect of temperature on solubility
As the temperature of the water increases, the amount of substance dissolved in the water also increases. This should be true for all types of substances.
Solubility refers to the ability of a given volume of solvent to dissolve a substance. It is normally expressed as the amount (in grams) of substance that can be dissolved in 100ml of a given solvent at room temperature (20 °C). Most substances will become more soluble when the temperature of the solution is increased.
Some factors that affect the solubility of a substance are temperature, air pressure and the type of solvent used. The solubility of different substances will not be the same for a given solvent. For example, some substances can dissolve very easily in water whereas others may not.
Saturation is reached when the substance cannot be dissolved in the solvent anymore. The remaining substance can be dissolved by adding more solvent or increasing the temperature of the solvent. When the temperature of such a saturated solvent is gradually reduced, crystals will start to form inside the solvent.