Question

How does ethanol reacts with
(a) metallic sodium
(b) acetic acid
(c) conc. H₂SO₄

Answer 1

1. Ethanol reacts with metallic sodium to yield sodium ethoxide and hydrogen gas. The equation is:

$\underset{\mathrm{Ethanol}}{2C_2{H}_5\mathrm{OH}}+2\mathrm{Na}\to \underset{\mathrm{Sodium}\mathrm{ethoxide}}{2C_2{H}_5\mathrm{ONa}}+H_2$

2. Ethanol reacts with acetic acid at high temperatures in the presence of concentrated sulphuric acid to form ethyl acetate (an ester). The equation for this is:

$\underset{\mathrm{Ethanol}}{C_2{H}_5\mathrm{OH}}+\underset{\mathrm{Acetic}\mathrm{Acid}}{{\mathrm{CH}}_3\mathrm{COOH}}$ ⇌ $\underset{\mathrm{Ethyl}\mathrm{ethanoate}}{{\mathrm{CH}}_3{\mathrm{COOC}}_2{H}_5}+H_{2}O$

This reaction is known as esterification reaction.

3. Ethanol is dehydrated by heating it with concentrated sulphuric acid to yield ethene at 170^oC. However, at 140^oC, ether is formed. The equation are as follows:

$\underset{\mathrm{Ethanol}}{C_2{H}_5\mathrm{OH}}\underset{170°C}{\overset{\mathrm{Conc}.H_2{\mathrm{SO}}_4}{\to }}\underset{\mathrm{Ethene}}{{\mathrm{CH}}_2={\mathrm{CH}}_2}+H_{2}O\underset{\mathrm{Ethanol}}{C_2{H}_5\mathrm{OH}}\underset{140°C}{\overset{\mathrm{Conc}.H_2{\mathrm{SO}}_4}{\to }}\underset{\mathrm{Ethoxyethane}}{C_2{H}_5{\mathrm{OC}}_2{H}_5}+H_{2}O$