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| Cleansing Action of Soaps |
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| The cleaning action of soap occurs when oil and grease are absorbed into the hydrophobic centers of soap micelles and are washed away. |
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| fig 7.10 - Cleansing action of soap |
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| Sodium lauryl sulphate is a synthetic detergent present in laundry soaps, toothpastes and shampoos. The formula of sodium lauryl sulphate is CH3(CH2)11SO4- Na+. It has a hydrophilic sulphate group and a hydrophobic dodecyl (C12H25) group. These detergent molecules are called 'anionics' because they have negative charge at the hydrophilic end. There are detergents which are 'cationics' that is they have positive charge at the hydrophilic end. For e.g., |
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| which is a quarternary ammonium compound. |
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| Many cationic detergents have germicidal properties and are therefore used in hospital disinfectants, mouthwashes and certain eyewetting solutions. |
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