concentration

The quantity of dissolved substance per unit quantity of a solution. Concentration is measured in various ways. The amount of substance dissolved per unit volume of the solution (symbol c) has units of mol dm⁻³ or mol l⁻¹. It is now called amount concentration (formerly molarity). The mass concentration (symbol ρ) is the mass of solute per unit volume of solution. It has units of kg dm⁻³, g cm⁻³, etc. The molality is the amount of substance per unit mass of solvent, commonly given in units of mol kg⁻¹. See also mole fraction.