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1 mole of an atom =

6.022 x atomic mass of 1 gram atoms

23
10 atoms the element

For Example :

23
• 1 Mole of N = contains 6.022 x 10 atoms of nitrogen

=14 grams

=1 gram atoms of nitroge

1 mole of ion

6.022 x 10 23 ions gram formula mass

For Example:
23
-2
1 Mole of (SO ) = contains 6.022 x 10 ions
4
= 96 grams

 MOLAR MASS
The mass of one mole of a substance in grams is called its molar mass.
For example :

Molar mass of water = 18.02 g mol-1
Molar mass of sodium chloride = 58.5 g mol-1