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प्रश्न
Would you be able to check if water is hard by using a detergent?
Would you be able to check whether water is hard by using a detergent? Why?
उत्तर १
Detergent gives lather with hard and soft water both, while a soap gives lather with soft water only. Thus, it is not possible to check if water is hard; by using a detergent.
उत्तर २
Detergents are ammonium or sulphonate salts of long chain carboxylic acids. Unlike soap,they do not react with calcium and magnesium ions present in hard water to form scum.They give a good amount of lather irrespective of whether the water is hard or soft. This means that detergents can be used in both soft and hard water. Therefore, it cannot be used to check whether the water is hard or not.
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संबंधित प्रश्न
Both soap and detergent are some type of salts. What is the difference between them?
Which of the following sets of materials can be used for conducting a saponification reaction for the preparation of soap?
(a) Ca(OH)2 and neem oil
(b) NaOH and neem oil
(c) NaOH and mineral oil
(d) Ca(OH)2 and mineral oil
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
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
Distinguish between esterfication and saponification reaction with the help of the chemical equations for each.
State one use of saponification process.
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
What change will you observe if you test soap solution with a litmus paper (red and blue)? Give reason for your observation.
State one advantage of soaps over detergent.
How is soap made? Write a word equation involved in soap making.
Describe the structure of a soap molecule with the help of a diagram.
Explain the cleansing action of soap. Draw diagrams to illustrate your answer.
Distinguish between esterification and saponification reactions of organic compounds.
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?
Explain why synthetic detergents are superior to soap.
Explain why often coloured spots are formed on clothes during washing.
What are the two different types of molecules found in the soap?
How does soap clean clothes?
The soap molecule has a
