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Question
State the methods by which hydrated salts can be made anhydrous.
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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