gmol

gmol, short for gram-molecule, is a historical or non-SI unit occasionally encountered in chemistry to denote the amount of substance expressed in grams equal to its molar mass. By definition, 1 gmol of a substance is the amount of substance whose mass in grams equals its molar mass in g/mol. Since molar mass is the mass per mole, 1 gmol of any substance corresponds to 1 mole, with the actual mass in grams depending on the substance (for example, 1 gmol of water weighs about 18.015 g, while 1 gmol of sodium chloride weighs about 58.44 g).

Convert between mass and amount: moles = mass (g) / molar mass (g/mol). The numeric value of the amount of substance in gmol is equal to the number of moles, so 2.5 mol equals 2.5 gmol. Conversely, knowing the mass and molar mass lets you compute moles, and that same value can be expressed as gmol.

Usage and status: gmol is not an SI unit and is rarely used in modern practice. The mole (mol) remains the standard SI unit for amount of substance, and molar mass is typically expressed in g/mol. The term gmol can cause confusion with g/mol, the unit of molar mass, so it is generally avoided in contemporary literature and communication.

See also: mole, molar mass, gram per mole (g/mol), SI units.