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SI Units: Mole

The mole is the amount of substance of a system that contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12.

When the mole is used, the elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles.

The SI unit of concentration (of amount of substance) is the mole per cubic meter (mol/m3).

For Students and Teachers

mole_front_webLeague of SI Superheroes – The Mole

This comic book-style video animation series has been developed to help middle school students learn about the 7 SI base measurement units. Able to sniff out and count the atoms of every element, the Mole is the king of chemistry. Equal to about 600 sextillion (that’s a 6 followed by 23 zeros!), a mole is a shorthand way to talk about huge numbers, especially of tiny things.