Amount of Substance

Amount of substance, abbreviated as n, is fundamental in chemistry, and is the quantity of a substance present, measured in terms of the number of particles (atoms, molecules, ions, etc.) that the substance contains.  The unit of measurement for amount of substance in the International System of Units (SI) is the mole (mol).

The mole is defined as the amount of substance that contains the same number of elementary entities (atoms, molecules, ions, etc.) as there are atoms in exactly 12 grams of carbon-12.  This number of entities is known as Avogadro's number.

The amount of substance is often used in stoichiometry, which involves the quantitative relationships between reactants and products in chemical reactions.  It allows chemists to predict the amounts of products formed from given reactants and vice versa, based on the balanced chemical equation and the stoichiometry of the reaction.

 

Amount of Substance formula
\( n = m\;/\;M\)
Symbol	English	Metric
\(n\) = Amount of Substance	-	\(mol\)
\(m\) = Mass	-	\(kg\)
\(M\) = Molar Mass	-	\(kg\;/\;mol\)