The rise is compressibility factor (`Z`) with increasing pressure of a gas is due to

Options

A. van der Waals constant `a`
B. van der Waals constant `b`
C. Both (`a`) and (`b`)
D. Not related to either `a` or `b`

Explanation

`(P+(a)/(V^(2)))(V-b)=RT`
Ignoring `a//V^(2)`, since `P` is large
`P(V-b)=RT`
`PV-Pb=RT`
Dividing by `RT`, we get
`(PV)/(RT)-(Pb)/(RT)=1`
`Z-(Pb)/(RT)=1`
`Z=1+(Pb)/(RT)`
`Z` increases as `b` increases, so it is independent of `a`.