SI Digital Framework
SI REFERENCE POINT
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mole

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1. The mole is the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12; its symbol is “mol”. 2. 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.

This definition is valid from 1971-10-04 to 2019-05-19
Unit mole
Symbol mol
Quantity amount of substance
Defining Resolution
CGPM Resolution 3 (1971)
Unit Type SI base unit
Notes:
  1. In the definition of the mole, it is understood that unbound atoms of carbon 12, at rest and in their ground state, are referred to.
  2. Note that this definition specifies at the same time the nature of the quantity whose unit is the mole.
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