Mole (mol)

What is mole?

In chemical reactions, quantities of substances are considered in terms of the number of atoms, ions or molecules present. The unit devised by chemists to express the number of atoms or ions or molecules is called mole (symbol "mol").

A Mole is defined as gram atomic mass, gram molecular mass or gram formula mass of any substances (atoms, ions or molecules) which contains 6.02e+23. entities/particles.

A mole is the amount of pure substances containing the same number of chemical units as there are atoms in exactly 12 grams of carbon-12 (i.e, 6.02e+23).

Formerly, the connotation of  "mole" was "gram molecular weight".

Current usage tends to apply the term "mole" to an amount containing Avogadro's number of whatever unit are being considered. Thus, it is possible to have a mole of atoms, ions, radicals, electrons, or quanta. This usage makes unnecessary such terms as "gram-atom", "gram-formula weight" etc.

Mole in light of Avogadro's number is defined as the mass in grams of atoms, molecules, or ions (gram atomic mass, gram molecular mass or gram formula maas) which contains avogadro's number of particles ( 6.02e+23).

For example:
1 mole of C atoms has mass of 12g.(Gram atomic mass or Molar mass)
1 mole of Mg atoms has mass of 24g.(Gram atomic mass or Molar mass)
1 mole of O2 molecules has a mass of 32g.(Gram molecular mass or Molar mass)
1 mole of NaCl has a mass of 58.5g.(Gram Formula mass or Molar mass)