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Question
Explain why soap cannot be used in hard water.
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Solution
Soaps cannot be used in hard water because they lose their cleansing property when used with it. Soaps do not form lather with hard water and instead form scum, as a result of which they lose their cleansing property.
RELATED QUESTIONS
While preparing soap a small quantity of common salt is generally added to the reaction mixture of vegetable oil and sodium hydroxide. Which one of the following may be the purpose of adding common salt?
(A) To reduce the basic nature of the soap
(B) To make the soap neutral
(C) To enhance the cleansing power of the soap
(D) To favour the precipitation of the soap
While studying the saponification reaction, what do you observe when you mix an equal amount of colourless vegetable oil and 20% aqueous solution of NaOH in a beaker?
(A) The colour of the mixture has become dark brown
(B) A brisk effervescence is taking place in the beaker
(C) The outer surface of the beaker has become hot
(D) The outer surface of the beaker has become cold
Why is soap not suitable for washing clothes when the water is hard?
A student is testing water to know which is best for cleansing purposes with soaps. He would find that the cleansing action of soaps is best when he uses water obtained from
(a) rain
(b) tap
(c) hand pump
(d) pond
Why are soaps not suitable for washing clothes when the water is hard?
Distinguish between esterification and saponification reactions of organic compounds.
What is meant by ‘surface activity’?
What are the differences between Soap and synthetic detergent?
Analogy:
Used to join components: Adhesives:: Clean the body ______.
- Write the formula and draw electron dot structure of carbon tetrachloride.
- What is saponification? Write the reaction involved in this process.
