DictionarymoleAmount of substance
noun

mole

The SI unit for amount of substance.

The chemist measures half a mole of sodium chloride.

Etymology

From German Mol, shortened from Molekül, “molecule.” The unit now counts entities of many kinds, not only molecules.

More examples

  • One mole of carbon contains exactly 6.02214076 × 10²³ carbon atoms.
  • Two moles of hydrogen gas react with one mole of oxygen gas.
  • We convert the sample's mass to moles before calculating the yield.

Forms

mole · moles

molar adjective — Expressed per mole of a substance.