SI unit of amount of substance
one mole contains exactly 6.02214076e23 entities (Avogadro's number)
bridges the atomic and macroscopic scales: one mole of carbon-12 has a mass of exactly 12 grams
enables stoichiometry: balanced equations give mole ratios of reactants and products
molar mass (g/mol) equals the atomic or molecular mass expressed in daltons
molar volume of an ideal gas at STP: 22.4 liters
molarity (mol/L) is the standard concentration unit in solution chemistry
named by Wilhelm Ostwald, derived from the German Molekul