Question

Calculate the total entropy change for the transition at $368$ K of $1$ mol of sulphur from the monoclinic to the rhombic solid state, is aH$=-401.7$ J $mo{l}^1$ for the transition. Assume the surroundings to be an ice-water both at $O^{o}C$.

• A. $-1.09J{K}^{-1}$
• B. $-0.5J{K}^{-1}$
• C. $-0.385J{K}^{-1}$
• D. None of these

Answer 1

Answer: (C)

$-0.385J{K}^{-1}$

Let consider the problem:

Total entropy change$=\frac{\Delta H}{T_2}-\frac{\Delta H}{T_1}$

$=\frac{-401.7}{273}-\left[\frac{-401.7}{368}\right]$

$=-0.38J/K.$