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प्रश्न
What is a soap? Name one soap.
उत्तर
Soap is a mixture of sodium or potassium salts of various natural fatty acids and oils, which when used with water show cleansing properties. A soap contains a large, non-ionic hydrocarbon group and an ionic group COO-Na+.
An example for a soap is sodium stearate (C17H35COO-Na+). It is a salt of sodium of fatty acid called stearic acid with a non-ionic hydrocarbon group C17H35, and an ionic carboxylate group COO- Na+.
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संबंधित प्रश्न
A student takes four test tubes marked P, Q, R and S of 25 mL capacity and fills 10 mL of distilled water in each. He dissolves one spoon full of four different salts in each as − KCl in P, NaCl in Q, CaCl2 in R and MgCl2 in S. He then adds about 2 mL of a sample of soap solution to each of the above test tubes. On shaking the contents of each of the test tubes, he is likely to observe a good amount of lather (foam) in the test tubes marked
(a) P and Q
(b) R and S
(c) P, Q and R
(d) P, Q and S
People use a variety of methods to wash clothes. Usually after adding the soap, they ‘beat’ the clothes on a stone, or beat it with a paddle, scrub with a brush or the mixture is agitated in a washing machine. Why is agitation necessary to get clean clothes?
Why does micelle formation take place when soap is added to water? Will a micelle be formed in other solvents such as ethanol also?
Explain the formation of scum when hard water is treated with soap.
Fill in the following blank with suitable word:
............. is better than soap 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
Differentiate between:
Detergents and Soaps.
Answer the following question.
In three test tubes A, B, and C, three different liquids namely, distilled water, underground water and distilled water in which a pinch of calcium sulphate is dissolved, respectively are taken. Equal amount of soap Answer is added to each test tube and the contents are shaken. In which test tube will the length of the foam (lather) be longest? Justify your answer.
The saponification of a fat or oil is done using _____ solution for hot process.
TFM in soaps represents ______ content in soap.
