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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.
Give two examples for Deliquescent substance.
Give one word for the following statement:
A substance which does not contain water .
Give the names and formulae of two substances
Anhydrous substance
State the methods by which hydrated salts can be made anhydrous.
What are hydrous substances? Explain with 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 |
Match the following
| 1. | Blue vitriol | CaSO4.2H2O |
| 2. | Gypsum | CaO |
| 3. | Deliquescence | CuSO4.5H2O |
| 4. | Hygroscopic | NaOH |
'A' is a blue coloured crystalline salt. On heating, it loses blue colour and to give 'B'. When water is added, 'B' gives back to 'A'. Identify A and B, write the equation.
