CBSE Class 10 Science 2017 · Paper 31/2 · Question 9

(a) Ethanol burns in air with a clean blue flame, forming carbon dioxide and water and releasing heat and light: ${\text{C}}_2{\text{H}}_5\text{OH}+3{\text{O}}_2⟶2{\text{CO}}_2+3{\text{H}}_2\text{O}+\text{heat and light}$ (b) Ethanol is dehydrated to ethene; the hot concentrated sulphuric acid acts as a dehydrating agent: ${\text{CH}}_3{\text{CH}}_2\text{OH}\underset{443\text{K}}{\overset{\text{hot conc. }{\text{H}}_2{\text{SO}}_4}{\to }}{\text{CH}}_2={\text{CH}}_2+{\text{H}}_2\text{O}$ (c) Sodium reacts with ethanol: hydrogen gas is given off (bubbles) and sodium ethoxide is formed: $2{\text{CH}}_3{\text{CH}}_2\text{OH}+2\text{Na}⟶2{\text{CH}}_3{\text{CH}}_2\text{ONa}+{\text{H}}_2$