Mole and Avogadro’s Number

Gram Atomic Mass - The atomic mass of an element expressed in gram is called gram atomic mass. It is also called 1 mole

e.g.

1gram atom of carbon = 12.00g = 1 mole of carbon atom 1 gram atom of nitrogen = 14.00g = 1 mole of nitrogen atom

Gram Molecular Mass - The molecular mass of an element or a compound expressed in gram is called gram molecular mass. It is also called 1 mole

e.g. 1 gram molecule of oxygen $O_2$ = 32.00g = 1 mole of oxygen molecule

Gram Formula Mass - The formula mass of an ionic compound expressed in grams is called gram formula mass. It is also called 1 mole

Mole - A mole is defined as “amount of substance containing equal to the Avogadro's number 6.02 x 10 ^23.

e.g.

1. 1 gram formula of $NaCl$ = 58.5g = 1 mole of $NaCl$

2. Atomic mass of $C$ is 12gram =1 mole of $C$ atom Molecular mass of $H_2SO_4$ is 98gram = 1mole of $H_2SO_4$

Number of moles =known mass of a substance / Molar mass of the substance

Avogadro’s Number - number of atoms, molecules or ions present in one mole The value is found to be 6.02x10^23

e.g.

1mole of $O_2$molecule = 32 g So 32gm of $O_2$ will contain $6.02x10^23$ molecule