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stavan110

physical chemistry...... mole concept......

basic formulae and tips.....

methods of calculations of mole:-

if no of some spieces is given than no of moles= given no of spieces/N_a
if weight is given than no of moles = given weight/ molar weight
the above formula can be used for compounds also...
if volume of a gas is given along with its temperature T and pressure P, than use n=PV/RT where R = 0.0821 lit-atm/mol(when p is in atmosphere and V in litre)
1 mole of any gases at STP occupies 22.4 litres....
Empirical formula is simple ratio formula of the compound.
molecular formula is the formula depictiong the actual no of atoms in one molecule of the compound....
molecular formula= empirical formula * n
n = molecular mass/ empirical formula mass