A mole of a substance can be defined as: #"A."#The number of atoms in a 12g sample of C-12 #"B."#The amount of substance that contains #6.02xx10^(23)# atoms #"C."#The quantity of a substance that contains one gram formula weight of the substance?

1 Answer
May 5, 2015

A mole is defined as A) The number of atoms in a 12 g sample of pure carbon-12, (which is #6.022xx10^23# atoms).

The International Bureau of Weights and Measures (BIMP) and the National Institute of Standards and Technology (NIST) in the U.S. defines the mole as the following:

  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 [12 grams] of carbon 12.
  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.

http://www.bipm.org/en/measurement-units/
http://physics.nist.gov/cuu/Units/current.html