Why Do Soaps Not Form Lather in Hard Water? - Science

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Why do soaps not form lather in hard water?

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Solution

Soaps do not form lather in hard water because

Hard water contains calcium and magnesium salts. Soap molecules react with calcium and magnesium salts to form an insoluble precipitate called scum.

Concept: Soap
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2014-2015 (March) All India Set 1

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