Ideal Gas Equation

Theory

After combining the three laws, Boyle's law, Charle's law and Avogadro's law, the final expression becomes,

The proportionality symbol is replaced by a constant, called as ideal gas constant.

or, PV = nRT
It is also called as ideal gas law and the value of R is 0.082 L atm mol^-1 K^-1 or 8.314 J mol^-1 K^-1
This law can be used to calculate value of any one of the four variables, provided we are given with the other three variables.

Applications of Ideal Gas Equation:

Molar Volume at Standard Temperature and Pressure (STP):
Standard temperature and pressure are considered as T = 0 ^oC and P = 1.00 atm. The volume occupied by one mole of any gas under these conditions is called the molar volume of an ideal gas. Using the ideal gas law, molar volume is 22.4 L.

Density of a gas:
Since density is simply mass/volume, the ideal gas equation can be rearranged to get the following equation:

where d is density and M is molar mass of the gas.