A dilute solution of ethanoic acid in water is called vinegar .
Physical properties :-
Colourless liquid having a sour taste and a smell of vinegar.
Boiling point is 118°C
On cooling , it freezes to form a colorless , ice-like solid ( like glacier) so it is also called glacial ethanoic / acetic acid.
Miscible with water in all proportions.
Chemical properties :-
Action on litmus -Turns blue litmus red ; universal indicator paper to orange ( 4 pH) showing it is a weak acid.
Reaction with Carbonates and Hydrogencarbonates :-
With Sodium Carbonate – Forms sodium ethanoate ( sodium acetate ) and CO2 gas.
2CH3COOH + Na3CO3 → 2CH3COONa + CO2 + H2O
With Sodium Hydrogencarbonate - Forms sodium ethanoate and evolves brisk effervescence of CO2 gas.
CH3COOH + NaHCO3 → CH3COONa + CO2 + H2O
Reaction with Sodium Hydroxide - It reacts with bases to form salt and water .
CH3COOH + NaOH → CH3COONa (sodium ethanoate)
Reaction with Alcohols - Reacts in presence of a little of Con. H2SO4 to form esters.
CH3COOH + C2H5OH → CH3COOC2H5+ H2O
Sweet smelling ester is formed. Esters are volatile liquids having sweet / pleasant / fruity smell . They are used to make artificial perfumes , flavours and essences .
Esters can be hydrolysed back to the alcohol and carboxylic acid when heated with sodium hydroxide solution.
CBSE Important Questions Class X Chemistry By : Mrs. Kritika Bhola