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प्रश्न
Why does hard water not form lather with soap?
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उत्तर
With soap, hard water generates scum/precipitate. Soap containing sodium stearate \[\ce{(C117H35COONa)}\] interacts with hard water to form calcium and magnesium stearate (\[\ce{Ca/Mg}\] stearate). As a result, it is unsuitable for laundering. Because of the deposition of salts in the form of scale, it is also hazardous to boilers.
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संबंधित प्रश्न
What causes the temporary and permanent hardness of water?
Discuss the principle and method of softening of hard water by synthetic ion-exchange resins.
What do you understand by
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What do you understand by
Permanent hard water
What are the causes for
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Explain with equation, what is noticed when permanent hard water is treated with
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Using given sample of temporary and permanent hard water, soft water, ordinary soap, detergent and washing soda how would you distinguish between temporary hard water and permanent hard water?
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Select the correct answer from the choice given in the options.
A substance which causes hardness in water _____.
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Hard water is not good for washing utensils.
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Take samples of water from different sources (like a tube well, a lake, a pond, or a river) and pour equal quantities of each sample of water into different test tubes. Measure the height of water in each test tube with a scale. Add one or two drops of liquid soap to each test tube. Shake each test tube five times and observe the height of the lather in each sample. Record your observations in the table. Which water is soft? Which water is hard? Can you say why?
