Mole mol
About the Mole
One mole contains exactly 6.02214076 × 10²³ elementary entities, the fixed value of the Avogadro constant. Until 2019 the mole was defined as the number of atoms in 12 grams of carbon-12, which tied it to the kilogram. Chemists use it to count atoms and molecules in quantities that can be weighed.
Related Units
Katal
kat1 kat = 1 mol/s
The katal is the catalytic activity that converts one mole of substrate per second. It was the most recent special name...
Metre
mBase unit; c = 299,792,458 m/s exactly
The metre is the length of the path travelled by light in vacuum in 1/299,792,458 of a second. It was first defined by...
Kilogram
kgBase unit; h = 6.62607015 × 10⁻³⁴ J·s exactly
The kilogram is defined by fixing the Planck constant at exactly 6.62607015 × 10⁻³⁴ joule-seconds. Until 20 May 2019 it...
Second
sBase unit; caesium-133 frequency = 9,192,631,770 Hz exactly
The second is defined by taking the unperturbed ground-state hyperfine transition frequency of the caesium-133 atom to...