The compressibility ratio of a gas is PV/nRT. What happen to the compressibility ratio if the attration force between the gas molecules increase? The answer says it decreases because the more molecules interact with each other, so the pressure they exert on the container decreases, thus compressibility ratio decreases. The part I dont understand is according to the real gas equation, real volume increases, and real pressure decreases. If it is true, then shouldnt the compressibility ration remain the same?