The compressibility factor for a real gas at high pressure is .

Options

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

Answer

b

Explanation

(b) van der Waals' equation for one mole of a real gas is
`(P+(a)/(V^(2)))(V-b)=RT`
`or" "PV=RT+Pb+(ab)/(V^(2))-(a)/(V)`
At high pressures, the van der Waals' gas equation reduces to PV =RT + Pb
`or " "(PV)/(RT)=1+(Pb)/(RT)`
`:.` Compressibility factor Z `=(PV)/(RT)=1+(Pb)/(RT)`