The van der Waal's equation of state for some gases can be expressed as :
`(P + (a)/( V^(2))) ( V - b) = RT`
Where `P` is the pressure , `V` is the molar volume , and `T` is the absolute temperature of the given sample of gas and `a, b , and R` are constants.
Which of the following does not have the same dimensional formula as that for `RT?`

Options

A. `(Kq)/(2a)`
B. `(Kq)/(3a)`
C. `(Kq)/(4a)`
D. `(Kq)/(6a)`

Answer

D

Explanation

Potential at `C=(Kq)/(3a)-(Kq)/(4a)+(Kq')/(3a)=0rArr q'=-q/4`
Potential at `A=(Kq)/(2a)-(Kq)/(4a)-(Kq/4)/(3a)=(Kq)/(6a)`
Hence `V_(A)-V_(C)=(Kq)/(6a)`