Chemistry MOLE CONCEPT

Basic Concept of Mole :

Atoms and molecules are extremely small in size and their numbers in even a small amount of any substance is really very large.

So, for handling such a large quantity, the concept of mole was introduced.

`1` mole`= 6.022 xx 10^23` species

A mole is the amount of substance that contains as many species [Atoms, molecules, ions or other particles] as there are atoms in exactly `12` `gm` of `C-12`.

`1` mole `= 6.022 xx 10^(23)` species

This number of species in 1 mol is known as Avogadro constant, denoted by `(N_A)`.

Methods to calculate Moles :

From number of particles :

`text(No. of mole)= text(Given no. of Paritcles [atoms/molecules/ ions])/(N_A)`

From given Mass :

(a) `text(For atoms: No. of mole)=text(Given mass of the substance[gm])/(text(Gram atomic mass))=text(No. of g-atoms)`

(b) `text(For molecules: No. of mole)=text(Given mass of the substance[gm])/(text(Gram atomic mass))=text(No. of g-molecules)`

From given volume of a Gas :

` n = (text(volume of gas at 1 atm and 273 K(in litre))/(22.4)`

MOLE CONCEPT

Basic Concept of Mole :

Methods to calculate Moles :

From number of particles :

From given Mass :

From given volume of a Gas :

T-Map