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.
1 If we know the molecular mass of the gas, we can convert this into grams/liter (mass/volume). 2  The molar mass (M) is the number of grams in one mole of a substance. 3  If we multiply both sides of the above equation by the molar mass: