Physics and Chemistry

Temperature, Measurement, and Methodology

What is a mole in chemistry?

A mole (mol), a fundamental measuring unit for the amount of a substance, refers to either a gram atomic weight or a gram molecular weight of a substance. It is the quantity of a substance that contains 6.02 x 1,023 atoms, molecules, or formula units of that substance. This number is called Avogadro’s number or constant after Amadeo Avogadro (1776–1856), who is considered to be one of the founders of physical science. Mole Day was organized by the National Mole Day Foundation to promote an awareness and enthusiasm for chemistry. It is celebrated each year on October 23.


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