The concentration of a solution depends on the amount of solute dissolved in the solvent. Concentrated solutions have a relatively large amount of solute per volume of solvent, while dilute solutions have a small amount. Saturated solutions contain the maximum amount of solute that can dissolve at a given temperature, while unsaturated solutions contain less. Supersaturated solutions contain more solute than is normally possible and are unstable. The solubility of a substance, or how much will dissolve, depends on factors like temperature and pressure.