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प्रश्न
State the methods by which hydrated salts can be made anhydrous.
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उत्तर
Hydrated salts can be converted to anhydrous substances by heating and also when exposed to dry air.
Example:
Glauber's salt becomes powdery anhydrous sodium sulphate when exposed to dry air.
\[\ce{Na2SO4.10H2O ->[dryair] NaSO4 + 10H2O}\]
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संबंधित प्रश्न
Define water of crystallization. Give two examples with formulae.
Give two examples for Deliquescent substance.
Give the names and formulae of two substances
Anhydrous substance
What are drying or desiccating agents? Give examples.
Differentiate between ‘hydrated’ & ‘anhydrous’ crystals. Give the chemical formula of – the following hydrated crystals -
(a) Washing soda
(b) Gypsum
(c) Blue vitriol
(d) Epsom salt
(e) Glauber’s salt.
State which crystal from (a) to (e) is a pentahydrate.
Complete the statement by filling the blank with the correct word from the option.
Hygroscopic substance absorb moisture from the atmosphere & _______their original state.
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.
Name or state the following:
A liquid hydroscopic substance.
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.
