GASEOUS STATES Maxwell’s Distribution of Velocities and Energies Calculation of Root Mean Square Velocity, Average Velocity and Most Probable Velocity Collision Diameter, Collision Number, Collision Frequency and Mean Free Path Deviation of Real Gases from Ideal Behaviour Derivation of Vander Waals equation of State Application of Vanderwaals Equation in Calculation of Boyle’s temperature Explanation of Behaviour of Real Gases Using Vander Waal’s Equation Critical Temperature Critical Pressure Critical Volume and their Determination