Standard unit for measuring everyday quantities of such minute entities as atoms or molecules. For any substance, the number of atoms or molecules in a mole is Avogadro's number (6.02 1023) of particles. Defined exactly, it is the amount of pure substance containing the same number of chemical units that there are in exactly 12 g of carbon-12. For each substance, a mole is its atomic weight, molecular weight, or formula weight in grams. The number of moles of a solute in a litre of solution is its molarity (M); the number of moles of solute in 1,000 g of solvent is its molality (m). The two measures differ slightly and have different uses. See also stoichiometry.
Variants of MOLE
mole or mol
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