JEE PYQ: Hydrogen Question 13
Question 13 - 2020 (05 Sep Shift 2)
The one that is NOT suitable for the removal of permanent hardness of water is:
(a) Clark’s method (b) Ion-exchange method (c) Calgon’s method (d) Treatment with sodium carbonate
Show Answer
Answer: (a)
Solution
Clark’s method is used to remove temporary hardness using lime water or $\text{Ca(OH)}_2$. It is not suitable for permanent hardness.