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Question
How will you check with the help of soap powder whether water is hard?
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Solution
- In hard water (from a well or a tube well), soap does not foam but instead creates scum.
- As a result, soap loses its cleaning ability. So, using soap, we can determine that the water is hard.
RELATED QUESTIONS
List two problems that arise due to the use of detergents instead of soaps.
A student requires hard water for an experiment in his laboratory which is not available in the neighbouring area. In the laboratory there are some salts, which when dissolved in distilled water can convert it into hard water. Select from the following groups of salts, a group, each salt of which when dissolved in distilled water will make it hard.
(A) Sodium chloride, Potassium chloride
(B) Sodium sulphate, Potassium sulphate
(C) Sodium sulphate, Calcium sulphate
(D) Calcium sulphate, Calcium chloride
Why is common salt (sodium chloride) added during the preparation of soap?
How is soap made? Write a word equation involved in soap making.
What is the advantage of detergents over soaps for washing clothes? Also state one disadvantage.
Explain the cleansing action of soap. Draw diagrams to illustrate your answer.
The chemical mostly used in the preparation of most of the soaps we use is
(a) Sodium chloride
(b) Potassium hydroxide
(c) Sodium hydroxide
(a) Potassium chloride
Explain why soap cannot be used in hard water.
Explain why synthetic detergents are superior to soap.
We are using ______ to remove strong stains on the clothes.
