# Question #8312f

##### 1 Answer
Oct 23, 2016

Avogadro's law is that if gases have the same number of molecules they will have the same partial pressure and as a result have the same volume.

#### Explanation:

This Law allows us to determine the number of moles in a sample of gas given its volume and that it is at standard temperature and pressure (0 celsius and 100KPa).

often displayed as,

$n = \frac{V}{22.71}$

$n = \text{number of moles of Gas molecules in moles}$
$V = \text{volume of gas at 1 Atm}$

The law is basically in simple terms that samples of gas with the same number of molecules will occupy the same amount of space (volume) if temperature and pressure are constant.

Another rule derived from this is,

$P V = n R T$

This follows the same "ideal" gas principle where,

$P = \text{pressure in kilopascals}$
$V = \text{volume in litres}$
$n = \text{number of moles}$
$R = \text{Gas constant} \left(8.314 J {K}^{-} 1 m o {l}^{-} 1\right)$
$T = \text{temperature in Kelvin}$

This is a relationship between gases and their volumes which as Avogadro's law suggests can be used for all gases.