Question

What happens when soap is vigorously mixed with distilled water in a test tube..plz answer it as fast as possible

Answer 1

When soap is vigorously mixed with distilled water, large amount of foam is formed. The reason is that distilled or soft water contains very less or negligible amount of mineral salts (mainly calcium and magnesium salts) as compared to hard water. The less the concentration of these salts in water, the more amount of foam is formed. Soap contains sodium stearate which reacts with calcium and magnesium salts forming insoluble stearates and instead of making the solution foamy, it makes it cloudy.
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