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प्रश्न
Select the correct word from the words in option to complete the sentence:
Efflorescence occurs when the vapour pressure of the hydrated crystals is ____ than the vapour pressure of the atmospheric humidity.
पर्याय
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उत्तर
Efflorescence occurs when the vapour pressure of the hydrated crystals is more than the vapour pressure of the atmospheric humidity.
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संबंधित प्रश्न
Define water of crystallization. Give two examples with formulae.
Give two examples of Crystalline anhydrous substances.
The process of separation or deposition of crystals from a hot saturated solution on gentle cooling of the solution is called ‘crystallization’. With reference to the statement explain what is meant by ‘water of crystallization. State which physical properties of a crystal are correlated with the water of crystallization.
Differentiate between an efflorescent, deliquescent & ‘ hygroscopic substance with suitable examples.
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 |
Explain the following observation:
In the expression anhydrous copper sulphate, what is meant by “anhydrous”?
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.
Give a reason for the following:
Heating a hydrated copper sulphate crystal is deemed a chemical change.
A hot saturated solution of copper sulphate forms crystals as it cools. Why?
