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प्रश्न
Why does the hardness of water render it unfit for use in a washing purposes.
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उत्तर
If hard water is used, calcium and magnesium ions of the water combine with the negative ions of the soap to form a slimy precipitate of insoluble calcium and magnesium usually called soap curd (scum).
Formation of soap curd will go on as long as calcium and magnesium ions are present. Till then, no soap lather will be formed and cleaning of clothes or body will not be possible. Moreover, these precipitates are difficult to wash from fabrics and sometimes form rusty spots if iron salts are present in water.
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संबंधित प्रश्न
Give reason for Table salt becomes moist during rainy season.
Discuss the importance of water as a solvent for our body .
'Water is the universal solvent'. Comment.
What is the importance of dissolved salts in water?
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Solvent
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A solution where solvent is a liquid other than water.
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The solute cannot be separated from a solution by filtration.
What is the advantage of a detergent over soap?
State whether the following statement is true or false.
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