Q22 of 30 Page 34

What happens when crystals of washing soda are left open in dry air? What is this change named as? Name two industries based on the use of washing soda.

When crystals of washing soda, i.e., Na2CO3.10H2O is left open in the dry air, it loses water of crystallization.

When we lose water molecule from any compound, we called this change as dehydration (removal of water)


Sodium carbonate is used in glass, soap and paper industries.


By far the largest consumption of sodium carbonate is in the manufacture of glass, paper, rayon, soaps, and detergents. It is also used as a water softener, since carbonate can precipitate the calcium and magnesium ions present in "hard" water.


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