Calculate $\Delta G_{f}^{\circ}$ At 325 K for Ethylene,C₂H₄(g),given the Thermodynamic Data Below

question 10

Multiple Choice

Calculate $\Delta G_{f}^{\circ}$ at 325 K for ethylene,C₂H₄(g) ,given the thermodynamic data below.
$\begin{array}{l}\begin{array}{lll}\text { Substance } & \Delta H_{\mathrm{f}}^{\circ}(\mathrm{kJ} / \mathrm{mol}) &S^{\circ}(\mathrm{kJ} / \mathrm{mol} \cdot \mathrm{K}) \\\hline \mathrm{C}(s) & 0.0 & +0.0057 \\\mathrm{H}_{2}(g) & 0.0 & +0.1306 \\\mathrm{C}_{2} \mathrm{H}_{4}(g) & +52.3 & +0.2195\end{array}\end{array}$

• A) ?47.1 kJ
• B) ?19.0 kJ
• C) +39.1 kJ
• D) +52.1 kJ
• E) +69.6 kJ

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