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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
Define water of crystallization. Give two examples with formulae.
Give two examples of Crystalline anhydrous substances.
Give two examples for Deliquescent substance.
What do you observe when Blue vitriol is heated?
The sticky substance formed when soap is added to hard water is ______.
What are drying or desiccating agents? Give examples.
Complete the following table:
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Common Name |
Chemical Name |
Formula |
Acid, base or salt |
Efflorescent, hygroscopic or deliquescent substance |
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Solid caustic potash |
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Quick lime |
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Oil of vitriol |
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Washing soda |
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Solid caustic soda |
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Blue vitriol |
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Explain the following observation:
Why is fused calcium chloride or cone, sulphuric acid used in a desiccator?
Differentiate between hydrated and anhydrous crystals with examples. State three defined changes that occur when hydrated copper sulphate is heated.
Name or state the following:
A liquid hydroscopic substance.
