Question

Temporary and permanent hardness of water can be removed by adding

Answer 1

Answer:

→Temporary Hardness can removed by-

a. By Boiling-

i. Mg(HCO₃)₂ + Heat ⇒Mg(OH)₂ + 2CO₂

ii. Ca(HCO₃)₂ + Heat ⇒CaCO₃ + H₂O + CO₂

.

b. Using Clark's Method-

i. Ca(HCO₃)₂ + Ca(OH)₂⇒2CaCO₃+ H₂O

ii. Mg(HCO₃)₂ + 2Ca(OH)₂⇒2CaCO₃+ Mg(OH)₂ + 2H₂O

→Temporary Hardness can removed by-

⇒Treatement with Washing Soda-

→MCl₂ + Na₂CO₃ = MCO₃+2NaCl

→MSO₄ + Na₂CO₃ = MCO₃+Na₂SO₄      (where M is Mg/Ca metal)