Question

If ∆H_vaporization of substance X (l) (molar mass: 30 g/mol) is 300 J/mol at it’s boiling point 300 K, then molar entropy change for reversible condensation process is 

(A) 30 J/mol K 

(B) -300 J/mol K 

(C) -30 J/mol K 

(D) None of these

Answer 1

Correct option (A) 30 J/mol K

Explanation:

 ∆H_vap = 300/g at T = 300 k 

= 300 × 30 J/mol