Superficial destruction of a surface by friction, pressure, ulceration, or trauma. The wearing away of a tooth by chemical or abrasive action. Also called odontolysis. erosion. The gradual wearing away of land surface materials, especially rocks, sediments, and soils, by the action of water, wind, or a glacier.
In chemistry, the molar mass M is a physical property defined as the mass of a given substance (chemical element or chemical compound) divided by its amount of substance. The base SI unit for molar mass is kg / mol.
As an example, the average molar mass of dry air is 28.97 g/mol. Related quantities. Molar mass is closely related to the relative molar mass (M r) of a compound, to the older term formula weight (F.W.), and to the standard atomic masses of its constituent elements.