Question

(a) What happens when ethanol reacts with ethanoic acid in the presence of a little of concentrated sulphuric acid? Write equation of the reaction involved.
(b) What happens when ethanol is heated with concentrated sulphuric acid at 170°C? Write the equation of the reaction which takes place.

Answer 1

(a) When ethanol reacts with ethanoic acid in the presence of a few drops of concentrated sulphuric acid, a sweet smelling ester named ethyl ethanoate is formed.

The chemical equation for the above reaction is:

${\mathrm{CH}}_3\mathrm{COOH}{+}_2{\mathrm{H}}_5\mathrm{OH}\stackrel{\mathrm{C}\mathrm{o}\mathrm{n}\mathrm{c}.{\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4}{\to }{\mathrm{CH}}_3{\mathrm{COOC}}_2{\mathrm{H}}_5{+\; H}_2\mathrm{O}$

(b) When ethanol is heated with concentrated sulphuric acid at 170^oC, it gets dehydrated to form ethene (unsaturated hydrocarbon). This reaction is termed as dehydration reaction as it involves the removal of water molecules from the alcohol (ethanol). In this reaction, the concentrated sulphuric acid acts as a dehydrating agent.

The chemical equation for the above reaction is:
CH₃CH₂OH → CH₂ =CH₂ + H₂O