Cleansing Agents

Cleansing Agents:-Soaps and Detergents are mainly used.

Soaps:-These are the sodium or potassium salts of long chain fatty acids e.g. palmitic acid, stearic acid.


Saponi fication:-The formarion of soap or sodium extra of long chain fatty acid by heating fat in aqueous NaoH.

Types of Soaps

  • Toilet Soap:- Prepared by using better grades of fat & oil. In these excess alkali are removed. These are made more attractive by adding colour & perfumes.
  • Transparent Soap:- Made by dissolving soap in ethanol.
  • Medicated Soap:-  Some medicinal value is added in soap.
  • Shaving Soap:- Contain glycerol to prevent rapid drying.
  • Laundry Soap:- Contain filters like sodium silicate etc.

Question:- Why do Soaps do not work in hard water?

Answer:-Hard water contains calcium and Magnesium salts

In these Ca & Mg form insoluble soap & they do not work.

Synthetic Detergents:-These are the salts of aromatic benzene sulphonates, that work in both soft as well as ward water.

Synthetic Detergents are classified into 3 categories

  1. Anionic Detergents:- These are the sodium salts of sulphonated long chain alcohols or hydrocarbons. In these anionic part of detergent participate. In cleansing action.

e.g. CH3(CH2)10 CH2 oSo3- Na+ Used in toothpaste also.

      2. Cationic Detergents:- These are quaternary ammonium salts of amines with acetates,  halides as anion. e.g.

     3. Non-Ionic Detergents:- They do not contain any ions. e.g. CH3(CH2)16(CH2)4 CH2CH2OH

Related Keywords
12    PMT    Chemistry    Chemistry in Everyday Life    Cleansing Agents