Which of the following is/are true?

Options

A. Higher the value of a, weaker is intermolecular force of attraction
B. At low pressure, `Z = 1 = (a)/(V_(m) RT)` , for ideal gas
C. `(V_(1))/(V_(2))= (T_(2))/(T_(1))^(3//2)` for reversible adiabatic expansion
D. A gas can be liquified below critical temperature at high pressure

Answer

B, C, D

Explanation

According to van der Waal.s equation `(p + (a)/(V_(m)^(2))) (V_(m) - b) = RT`
At low pressure `V_(m)` is high so .b. can be neglected , `(P + (a)/(V^(2))) V = RT`
`pV_(m) + (a)/(V_(m)) = RT , (p V_(m))/(RT) + (a)/(V_(m) RT) = 1 , Z + (a)/(V_(m) RT) = 1 , Z = 1 - (a)/(V_(m) RT)`
`(V_(1))/(V_(2)) = ((T_(2))/(T_(1)))^(3//2)` for reversible adiabatic expansion.