Correct Answer - A `rarr` (2, 4) B `rarr` (2) C. `rarr` (3) D. `rarr`(1)

A. Enthpy of vaporisation is always positive. It is equal to `Delta H_("vap") //T_(b)`

B. `Delta_(r) G^(@) = - RT ln K`

If K is positive, `Delta_(r)G^(@)` = negative and reaction is spontaneous.

C. Crystalline solid state has lowest entropy.

D. During adiabatic expansion of a ideal gas, `q = 0`, Hence, `Delta U = q + W` gives `Delta U = W`, i.e., work done is at the cost of internal energy which decreases.