1.14.66: Spontaneous Chemical Reaction
A closed reaction vessel at \(298.2 \mathrm{~K}\) and \(101325 \mathrm{~N m}^{-2}\) is filled with a solution having the initial composition, water (\(1.2 \mathrm{~mol}\)), \(\mathrm{NaOH}(\mathrm{aq}, 0.5 \mathrm{~mol})\), \(\mathrm{CH}_{3}.\mathrm{COOC}_{2}\mathrm{H}_{5}(\mathrm{aq}, 0.2 \mathrm{~mol})\). Experiment shows that the system spontaneously changes composition. We write the overall chemical reaction as:
\[\mathrm{CH}_{3} \mathrm{COOC}_{2} \mathrm{H}_{5}+\mathrm{OH}^{-} \rightarrow \mathrm{CH}_{3} \mathrm{COO}^{-}+\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH} \nonumber \]
In this connection we state that the reaction is driven by the affinity for spontaneous reaction leading to a change in chemical composition characterized by the extent of reaction, \(\xi\).