MOLE (noun)

 

Abbreviated as "mol." The amount of a substance that contains the same number of elementary entities as there are atoms in exactly 12 grams of ¹²₆ C, which is 6.02205 * 10²³; hence Avogadro's number is 6.02005 * 10²³ / mol.

NOTE: The mole is the most important concept when it comes to laboratory chemistry concepts as it is used in almost all calculations. See the section on "Mole" in the Primer.