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प्रश्न
Differentiate the function of concentrated sulphuric acid as a drying agent & as a dehydrating agent. Is fused calcium chloride a dehydrating or a desiccating agent. Give reasons.
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उत्तर
Sulphuric acid (cone.) acts as drying agent when it removes water from other substances i.e. for drying gases.
Cone, sulphuric acid acts as dehydrating agent when it removes chemically combined water from compounds due to it strong affinity for water.
\[\ce{\underset{\text{ethanol}}{C2H5OH} + ->[Conc. H2SO4][dehydrating agent] \underset{\text{ethene}}{C2H4} +\underset{\text{water}}{H2O}}\]
Cone. H2SO4 has removed H20 from ethanol and changed it to ethene. Fused calcium chloride [CaCl2] is desiccating agent as it is drying the substance.
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संबंधित प्रश्न
The sticky substance formed when soap is added to hard water is ______.
Give the names and formulae of two substances.
Hydrated substance
The substance that can remove hydrogen and oxygen atoms in the ratio of 2:1(in the form of water) from the compound.
State the methods by which hydrated salts can be made anhydrous.
Match the substances in List I with the appropriate answer in List II.
| List I | List II |
| 1. Green vitriol | A: Permanent hardness in water |
| 2. Paint | B: Hygroscopic |
| 3. Magnesium chloride | C: Temporary hardness in water |
| 4. Magnesium bicarbonate | D: Heptahydrate |
| 5. Calcium oxide | E: Colloidal |
Select the correct word from the words in option to complete the sentence:
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Select the correct answer from the choice given in the options.
An anhydrous crystal _____.
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