Question

Properties of gases are easier to understand than those of solids and liquids. This is mainly because in a gas, molecules are far from each other and their mutual interactions are negligible except when two molecules collide. The perfect gas equation can be written as PV = µRT where µ is the number of moles and R = NA kB is a universal constant. The temperature T is absolute temperature. Choosing kelvin scale for absolute temperature, R = 8.314 J mol-1K-1. If we fix µ and T in the equation, we get PV = constant i.e., keeping temperature constant, pressure of a given mass of gas varies inversely with volume. This is the famous Boyle's law. Next, if you fix P, shows that V ∝ T i.e., for a fixed pressure, the volume of a gas is proportional to its absolute temperature T (Charles' law).