Avogadro's law is an experimental gas law relating the volume of a gas to the amount of substance of gas present. The law is approximately valid for real gases at sufficiently low pressures and high temperatures.
Avogadro's law states that, "equal volumes of all gases, at the same temperature and pressure, have the same number of molecules."
For a given mass of an ideal gas, the volume and amount (moles) of the gas are directly proportional if the temperature and pressure are constant.
Scientific form of Avogadro’s Law is : V ÷ n = k , this means that the volume amount fraction will always be the same value if the pressure and temperature remain constant.
The container holding the gas is flexible in some way and can expand or contract because the volume is one of the variables.
If the amount of gas in a container is amplified, the volume upsurges.
If the quantity of gas in a container is reduced, the volume declines.