During the preparation of a yellow precipitation from one mole of ${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$ in basic medium number moles of Iodine required is __________.

$\begin{array}{r}2\mathrm{NaOH}+{\mathrm{I}}_2\to \underset{\text{ Sodium iodide }}{\mathrm{NaI}}+\underset{\text{ Sodium hypoiodide }}{\mathrm{NaOI}}+{\mathrm{H}}_2\mathrm{O}.\\ {\mathrm{RCOCH}}_3+3\mathrm{NaOI}\to \underset{\text{ Iodoform }}{\mathrm{RCOONa}}+\underset{\text{ (Y ellow ppt.) }}{{\mathrm{CHI}}_3}+2\mathrm{NaOH}\\ \mathrm{RCH}\left(\mathrm{OH}\right){\mathrm{CH}}_3+3\mathrm{NaOI}\to \underset{\text{ Iodoform }}{\mathrm{RCOONa}}+\underset{\text{ (Y ellow ppt.) }}{{\mathrm{CHI}}_3}+2\mathrm{NaOH}\end{array}$