Molar mass (M) is the mass of one mole of a substance, expressed in grams per mole. It provides the conversion between the mass of a sample and the amount of substance it contains, which is needed in nearly all quantitative chemistry. Numerically, the molar mass in grams per mole equals the relative atomic or molecular mass.

摩尔质量(M)是 1 摩尔物质的质量,单位为克每摩尔。它提供了样品质量与其所含物质的量之间的换算,几乎一切定量化学都需要它。在数值上,以克每摩尔为单位的摩尔质量等于相对原子质量或相对分子质量。