Carbon and Its Compounds

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 + Na₂CO₃ ? 2 CH₃COONa + 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 + H₂O
   ( sodium ethanoate)
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 .

SOAPS  AND  DETERGENTS

Detergent – Any substance which has cleansing action in water.
Two types  ---  Soapy and Non soapy ( detergents)

Soaps  -- Sodium or potassium salt of a long chain carboxylic acid( fatty acid) which has cleansing properties in water. It has a large non-ionic hydrocarbon group and an ionic group  , COONa.
Eg. Sodium Stearate – C₁₇ H₃₅COONa
       Sodium Palmitate  -  C₁₅H₃₁COONa

• Soap is the salt of a strong base ( sodium hydroxide) and a weak acid So a solution of soap in water is basic in nature.

Submitted By Mrs. Kritika Bhola
Email Id : kritikabhola@yahoo.co.in