When enthanol is heated with conc. H 2 SO 4 , a gas is produced. The compound formed, when this gas is…

Ethanol undergoes dehydration by heating it with concentrated ${\mathrm{H}}_2{\mathrm{SO}}_4$ at $443 \mathrm{K}$.

${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}\underset{443 \mathrm{K}}{\overset{{\mathrm{H}}_2{\mathrm{SO}}_4}{\to }}{\mathrm{CH}}_2={\mathrm{CH}}_2+{\mathrm{H}}_2\mathrm{O}$

Alkenes on reaction with cold, dilute, aqueous solution of potassium permanganate (Baeyer’s reagent) produce vicinal glycols. Decolorisatlon of ${\mathrm{KMnO}}_4$ solution is used as a test for unsaturation.