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CHEMISTRY CBSE CLASS X

Ethanoic Acid (Acetic Acid - CH₃COOH)

A dilute solution of ethanoic acid in water is called vinegar .

Physical  properties :-

1. Colourless liquid having a sour taste and a smell of vinegar.
2. Boiling point is 118°C
3. On cooling , it freezes to form a colorless , ice-like solid ( like glacier) so it is also called glacial ethanoic / acetic acid.
4. Miscible with water in all proportions.

Chemical properties :-

1. Action on litmus -Turns blue litmus  red ; universal indicator paper to orange ( 4 pH)  showing it is a weak acid.
2. Reaction with Carbonates and Hydrogencarbonates :-
   
   
   1. With Sodium Carbonate – Forms sodium ethanoate ( sodium acetate ) and CO₂ gas.
      2CH₃COOH + Na₃CO₃ → 2CH₃COONa + CO₂ + H₂O
      
      
   2. With Sodium Hydrogencarbonate - Forms sodium ethanoate and evolves brisk effervescence of CO₂ gas.
      CH₃COOH + NaHCO₃ → CH₃COONa + CO₂ + H₂O
      
      
3. Reaction with Sodium Hydroxide - It reacts with bases to form salt and water .
   CH₃COOH + NaOH → CH₃COONa (sodium  ethanoate) + H₂O
   
   
4. 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.

Submitted By Mrs. Kritika Bhola
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