a
\(\begin{gathered}
Ph - COOH + NaH\mathop C\limits^* {O_3} \rightleftarrows {H_2}\mathop C\limits^* {O_3} + Ph - CO{O^\Theta } \hfill \\
\mathop {{H_2}\mathop C\limits^* {O_3}}\limits_{{\text{unstable}}} \to \mathop C\limits^* {O_2} \uparrow + {H_2}O \hfill \\
\end{gathered} \)