Estimate the boiling point of ethanol, C₂H₅OH, using the given the following thermodynamic parameters. $$\begin{array} { l l l } & \mathrm { C } _ { 2 } \mathrm { H } _ { 5 } \mathrm { OH }(\ell)& \mathrm { C } _ { 2 } \mathrm { H } _ { 5 } \mathrm { OH } ( \mathrm { g } ) \ \hline \Delta _ { f } H ^ { \circ } ( \mathrm { kJ } / \mathrm { mol } ) & - 277.0 & - 235.3 \ S ^ { \circ } ( \mathrm { J } / \mathrm { K } \cdot \mathrm { mol } ) & 160.7 & 282.7 \ \Delta _ { f } G ^ { \circ } ( \mathrm { kJ } / \mathrm { mol } ) & - 174.7 & - 168.5 \end{array}$$

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The boiling point can be estimated using the Gibbs free energy change for the phase transition, ΔG = ΔH - TΔS. At boiling point, ΔG = 0. Calculate ΔH and ΔS for vaporization: ΔH = -235.3 - (-277.0) = 41.7 kJ/mol, ΔS = 282.7 - 160.7 = 122 J/mol·K. Convert ΔH to J/mol: 41.7 kJ/mol = 41700 J/mol. Set 0 = 41700 - T(122) and solve for T: T = 41700 / 122 = 341.8 K, which is approximately 69 °C.

Estimate the Boiling Point of Ethanol, C2H5OH, Using the Given

Estimate the Boiling Point of Ethanol, C₂H₅OH, Using the Given