Avogadros Law and the Standard Molar Volume

Many experiments have demonstrated that Avogadro s hypothesis is accurate to within about 2%, and the statement is now known as Avogadro s Law. 

At constant temperature and pressure, the volume, V, occupied by a gas sample is directly proportional to the number of moles, n, of gas. 

For two samples of gas at the same temperature and pressure, the relation between volumes and numbei s of moles can be represented as 

The volume occupied by a mole of gas at standard temperature and pressure, STP, is referred to as the standard molar volume. It is nearly constant for all gases (Table 12-3). 

The standard molar volume of an ideal gas is taken to be 22.414 liters per mole at STP. 

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