Question

Distinguish between alkaline and non alkaline hardness?

Answer 1

TEMPORARY OR ALKALINE HARDNESS	PERMANENET OR NON-ALKALINE HARDNESS
1. Caused by the process of dissolved bicarbonates of calcium, magnesium and other heavy metals and the carbonates of iron. salts responsible for temporary hardness are ca( Hco3)2' Mg(Hco3)2.	1.lt is due to presence of dissolved chlorides and sulphates of calcium, magnesium, iron and other heavy metals.
2. Temporary Hardness can be removed by boiling water.	2.Permanent Hardness cannot be removed by boiling the water.
3. Temporary hardness is called as carbonates or alkaline hardness.	3.!t is also known as non-carbonates or non-alkaline hardness.
4. Boiling: ca(Hco3)2 → CaC03 + co2 + H20. Mg(HCO3)2  → Mg(OH)2 +2CO2.	4.Can be removed by using chemical and not by boiling e.g. Lime soda method. CaCI2 +Na2CO3 → CaCO3 +2NaCI.