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प्रश्न
Give the reason of formation of scum when soaps are used with hard water.
उत्तर
When soaps are used with hard water they form scum. This is caused by the reaction of soap with the calcium and magnesium salts, which cause the hardness of water.
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संबंधित प्रश्न
Why do soaps not form lather in hard water?
Hard water is not available for an experiment. Some salts are given below :
(I) Sodium chloride
(II) Sodium sulphate
(III) Calcium chloride
(IV) Calcium sulphate
(V) Potassium chloride
(VI) Magnesium sulphate
Select from the following group of these salts, each member of which may be dissolved in water to make it hard.
(A) I, II, V
(B) I, III, V
(C) III, IV, VI
(D) II, IV, VI
Fill in the following blank with suitable word:
The sodium salt of a long chain fatty acid is called .............
Use of synthetic detergents causes pollution of water.
Which of the two is better for washing clothes when the water is hard: soap or detergent? Give reason for your answer.
How is soap made? Write a word equation involved in soap making.
The soap molecule has a ______.
What is the difference between soaps and detergents? State, in brief, the cleansing action of soaps in removing an oily spot from a fabric. Why are soaps not very effective when a fabric is washed in hard water? How is this problem resolved?
What is meant by 'surface activity'?
TFM in soaps represents ______ content in soap.
