Amount of a constituent
divided by the total amount of all constituents in the mixture. It is also called mole fraction. Amount fraction is equal to the number fraction
: the number of entities
of one constituent
divided by the total number of entities
in the mixture.
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook