Explanation:
$\begin{array}{*{20}{c}}
{C{H_3} - CH - COONa} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_2} - COONa}
\end{array}$ $\xrightarrow[{Electrolysis}]{{{H_2}O}}$ $\mathop {C{H_3} - CH = C{H_2}}\limits_{{\text{propene}}} $