# Question 19.5: Calculating ΔG° from Standard Free Energies of Formation Cal...

Calculating $\Delta G^{\circ}$ from Standard Free Energies of Formation

Calculate $\Delta G^{\circ}$ for the combustion of $1 \mathrm{~mol}$ of ethanol, $\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}$, at $25^{\circ} \mathrm{C}$.

$\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}(l)+3 \mathrm{O}_{2}(g) \longrightarrow 2 \mathrm{CO}_{2}(g)+3 \mathrm{H}_{2} \mathrm{O}(g)$

Use the standard free energies of formation given in Table 19.2.

PROBLEM STRATEGY

Calculate $\Delta G^{\circ}$ from $\Delta G_{f}^{\circ}$ values, similar to the way you calculate $\Delta H^{\circ}$ from $\Delta H_{f}^{\circ}$.

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Question: 19.10

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a. From Tables 6.2 and 19.1, you have  \beg...
Question: 19.4

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Write the balanced equation and place below each f...
Question: 19.3

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It is convenient to put the standard entropy value...
Question: 19.9

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You first calculate \Delta G^{\circ}[/latex...
Question: 19.8

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Question: 19.7

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a. Note that \mathrm{H}_{2} \mathrm{O}[/lat...
Question: 19.6

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The problem is set up as follows:  \begin{...
Question: 19.2

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When liquid $\mathrm{CCl}_{4}$ evapor...