Answer:
1 - Crystallisation is the process of formation of solid crystals from solution, melt or by deposition directly from a gas phase.
2 - Mg (HCO3)2 Magnesium Hydrogen Carbonate and Ca (HCO3)2 Calcium bicarbonate cause temporary hardness in water.
3 - Permanent hardness is caused by dissolved chloride, sulfate, and nitrates of Calcium & magnesium (which are not removed by boiling)and temporary hardness is caused by dissolved calcium hydrogen carbonate (which is removed by boiling).
4 - Addition of washing soda can remove both temporary as well as permanent hardness of water.
5 - A hygroscopic substance is one that readily attracts water from its surroundings, through either absorption or adsorption. Examples include honey, glycerin, ethanol, methanol, concentrated sulfuric acid, and concentrated sodium hydroxide (lye).
Explanation:
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