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Which one of the following statements about the cleansing action of soap is not true?

Options

  1. AThe oil and dirt gets collected in the centre of the micelle.
  2. BSoap micelles scatter light.
  3. CSoaps are ammonium salts of long chain carboxylic acids.
  4. DSoap forms insolubleprecipitates with the calcium and magnesium ions in hard water.

Correct answer

C. Soaps are ammonium salts of long chain carboxylic acids.

Step-by-step solution

Soap are sodium or potassium salts of long chain fatty acids. - Soap is a kind of molecule in which both the ends have different properties. - Hydrophilic end and Hydrophobic end - The first one is the hydrophilic end which dissolves water and is attracted to it whereas the second one is the hydrophobic end that is dissolved in hydrocarbons and is water repulsive in nature. If on the surface of the water, soap is present then the hydrophobic tail which is not soluble in water will align along the water surface. - T

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