Lawrie Ryan and Roger Norris Solutions for Chapter: Entropy and Gibbs Free Energy, Exercise 8: Question

Calculate the total entropy change in each of the following reactions using the standard molar entropy values given here.

Values for:

 $$\begin{gathered} {\mathrm{S}}^{⊝} \mathrm{in} \mathrm{J} {\mathrm{K}}^{-1} {\mathrm{mol}}^{-1}. \\ \mathrm{Given}: \\ \mathrm{S}\left(\mathrm{s}\right)=31.80 \\ {\mathrm{H}}_2\left(\mathrm{g}\right)=130.6 \\ {\mathrm{H}}_2\mathrm{S}\left(\mathrm{g}\right)=205.7 \\ \mathrm{S}\left(\mathrm{s}\right)+{\mathrm{H}}_2\left(\mathrm{g}\right)\to {\mathrm{H}}_2\mathrm{S}\left(\mathrm{g}\right); ∆{\mathrm{H}}_{\mathrm{reaction}}^{⊝}=-20.6 \mathrm{kJ} {\mathrm{mol}}^{-1}. \end{gathered}$$

Calculate the total entropy change in each of the following reactions using the standard molar entropy values given here.

Values for

 $$\begin{gathered} {\mathrm{S}}^{⊝} \mathrm{in} \mathrm{J} {\mathrm{K}}^{-1} {\mathrm{mol}}^{-1}. \\ \mathrm{Given}: \\ \mathrm{C}\left(\mathrm{graphite}\right)=5.700 \\ {\mathrm{N}}_2\left(\mathrm{g}\right)=191.6 \\ {\mathrm{C}}_2{\mathrm{N}}_2\left(\mathrm{g}\right)=242.1 \\ 2\mathrm{C}\left(\mathrm{graphite}\right)+{\mathrm{N}}_2\left(\mathrm{g}\right)\to {\mathrm{C}}_2{\mathrm{N}}_2\left(\mathrm{g}\right); ∆{\mathrm{H}}_{\mathrm{reaction}}^{⊝}=+307.9 \mathrm{kJ} {\mathrm{mol}}^{-1}. \end{gathered}$$

Calculate the total entropy change in each of the following reactions using the standard molar entropy values given here.

Values for

$$\begin{gathered} {\mathrm{S}}^{⊝} \mathrm{in} \mathrm{J} {\mathrm{K}}^{-1} {\mathrm{mol}}^{-1}. \\ \mathrm{Given}: \\ \mathrm{P}\left(\mathrm{s}\right)=41.10 \\ {\mathrm{O}}_2\left(\mathrm{g}\right)=205.0 \\ {\mathrm{P}}_4{\mathrm{O}}_{10}\left(\mathrm{s}\right)=228.9 \\ 4\mathrm{P}\left(\mathrm{s}\right)+5{\mathrm{O}}_2\left(\mathrm{g}\right)\to {\mathrm{P}}_4{\mathrm{O}}_{10}\left(\mathrm{s}\right); ∆{\mathrm{H}}_{\mathrm{reaction}}^{⊝}=-2984.0 \mathrm{kJ} {\mathrm{mol}}^{-1}. \end{gathered}$$

Calculate the total entropy change in each of the following reactions using the standard molar entropy values given here.

Values for

$$\begin{gathered} {\mathrm{S}}^{⊝} \mathrm{in} \mathrm{J} {\mathrm{K}}^{-1} {\mathrm{mol}}^{-1}. \\ \mathrm{Given}: \\ {\mathrm{C}}_3{\mathrm{H}}_8\left(\mathrm{g}\right)=269.9 \\ {\mathrm{O}}_2\left(\mathrm{g}\right)=205.0 \\ {\mathrm{CO}}_2\left(\mathrm{g}\right)=213.6 \\ {\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)=69.90 \\ {\mathrm{C}}_3{\mathrm{H}}_8\left(\mathrm{g}\right)+5{\mathrm{O}}_2\left(\mathrm{g}\right)\to 3{\mathrm{CO}}_2\left(\mathrm{g}\right)+4{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right); ∆{\mathrm{H}}_{\mathrm{reaction}}^{⊝}=-2219.2 \mathrm{kJ} {\mathrm{mol}}^{-1}. \end{gathered}$$