Physical Chemistry Real gases Compression Factors Real gases do not obey the perfect gas equation exactly. The real gas is expressed as the compression factor a ehavior of a measure of the deviation from ideality of the be P (,1RT (8. 200K .20C CH, 500K N 1000K CHA 1000K 200K P 100200300 300600900Compression Factors Real gases do not obey the perfect gas equation exactly. The measure of the deviation from ideality of the behavior of a real gas is expressed as the compression factor Z: RT PV Z P T m ( , )  (8.1) Real Gases Z P 200 K 500 K 1000 K 200 K 1000 K 0 300 600 900 3 2 1 0 CH4 Z P H2 0 100 200 300 1.2 1 0.8 0 0 oC N2 CH4 Physical Chemistry