|Name, symbol||carbon 12 isotope,12C|
|Parent isotopes||12NTemplate:Infobox isotope/Decay|
|Isotope mass||12 u|
|Excess energy||0± 0 keV|
|Binding energy||92,161.753± 0.014 keV|
Prior to 1959 both the IUPAP and IUPAC tended to use oxygen to define the mole, the chemists defining the mole as the number of atoms of oxygen which had mass 16 g, the physicists using a similar definition but with the oxygen-16 isotope only. The two organizations agreed in 1959/1960 to define the mole as:
This was adopted by the CIPM (International Committee for Weights and Measures) in 1967, and in 1971 it was adopted by the 14th CGPM (General Conference on Weights and Measures).