$\begin{matrix}
\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O \\
\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|| \\
Ph-CH-C-H \\
|\,\,\,\,\,\,\,\,\,\, \\
OH\,\,\,\,\,\,\, \\
\end{matrix}\,\xrightarrow[{{H}_{2}}O]{H{{O}^{\Theta }}}\,(B)$ ; $(A)$ and $(B)$ are isomer and isomerization effectively carried out by trace of base $(B)$ . Identify $(B)$
→Assuming that water vapour is an ideal gas, the internal energy change $(\Delta U)$ when $1\, mol$ of water is vapourised at $1\, bar$ pressure and $100\,^oC,$ (given : molar enthalpy of vapourisation of water at $1\, bar$ and $373\, K = 41\, kJ\, mol^{-1}$ and $R = 8.3\, J\, mol^{-1}\, K^{-1}$) will be .............. $\mathrm{kJ\,mol}^{-1}$
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