At 298 ,K the following standard molar entropies are known: Calculate for the…

CHEMISTRY · Subjective · A Level · Chemistry · Thermodynamics · Thermodynamics

Problem

At 298\,K the following standard molar entropies are known:

S^{\circ}(\text{SO}_2\,(g)) = 248\;\text{J}\,\text{mol}^{-1}\,\text{K}^{-1}

S^{\circ}(\text{O}_2\,(g)) = 205\;\text{J}\,\text{mol}^{-1}\,\text{K}^{-1}

S^{\circ}(\text{SO}_3\,(g)) = 257\;\text{J}\,\text{mol}^{-1}\,\text{K}^{-1}

Calculate

\Delta S^{\circ}

for the reaction

2\,\text{SO}_2\,(g) + \text{O}_2\,(g) \longrightarrow 2\,\text{SO}_3\,(g)

at 298\,K, and express your answer in

\text{kJ}\,\text{mol}^{-1}\,\text{K}^{-1}

to two significant figures.