Problem 4J.15) 7th edition of the textbook

$\Delta G^{\circ}= \Delta H^{\circ} - T \Delta S^{\circ}$

$\Delta G^{\circ}= -RT\ln K$

$\Delta G^{\circ}= \sum \Delta G_{f}^{\circ}(products) - \sum \Delta G_{f}^{\circ}(reactants)$

Katie Frei 1L
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Problem 4J.15) 7th edition of the textbook

In problem 4J.15) of the 7th edition of the textbook, you have to calculate the standard entropy of the compound SO2(g). To do this you set up the chemical equation which is S(s) + O2(g) produces SO2(g). In order to find the standard entropy, I had to look at the value of molar entropy for S(s), which gave two options in appendix 2A: S(s), rhombic and S(s), monoclinic. What do these two different options mean, and how do I know which one to use when calculating the standard entropy of SO2(g)?

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Re: Problem 4J.15) 7th edition of the textbook

The two numbers you see correspond to two crystal structures that S can form. At room temperature, the rhombic phase is more stable.