\(C{H_2}OH - CHOH - C{H_2}OH\xrightarrow[{or\,{H_2}S{O_4}\,,\,\Delta }]{{KHS{O_4}\,\,or\,\,{P_2}{O_5}}}\,C{H_2} = CH - CHO\, + \,2{H_2}O\)
ફિનોલ $\xrightarrow{{Zn}}A\xrightarrow[{HN{O_3},{{60}\,^o}C}]{{{H_2}S{O_4}}}B\xrightarrow[{NaOH{_{(aq)}}}]{{Zn}}C$