Thermodynamics · Question 77

The entropy change in the fusion of one mole of a solid melting at 27 (latent heat of fusion is 2930 J mol-1) is :

1. 9.77 J/mol-K
2. 10.77 J/mol-K
3. 9.07 J/mol-K
4. 0.977 J/mol-K

Answer

(1) 9.77 J/mol-K

Solution

As per NCERT, for a phase change at its transition temperature, fusS = fusHTf

Tf = 27 + 273 = 300 K

⇒ fusS = 2930300

= 9.77 J mol-1 K-1

Answer: (1)