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Question
State the methods by which hydrated salts can be made anhydrous.
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Solution
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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| 1. Green vitriol | A: Permanent hardness in water |
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