Homogeneous mixing and compressibility both result from the fact that the molecules are far apart in gases. Mixing occurs because individual gaseous molecules have little interaction with their neighbours, assuming that no reaction taken place, the chemical identities is possible in gases because only about 0.1% of the volume of a typical gas is taken up by the molecules themselves under normal circumstances, the remaining 99.9% is empty space
Compressibility factor of a gas is given by

Options

A. `(PV)/(RT)`
B. `(1+(Pb)/(RT))`
C. `(1-a/(RTV))`
D. `(1+(RT)/(Pb))`

Answer

B