Question

The salt responsible for permanent hardness of $H_{2}O$ is

• A. $N{a}_{2}S{O}_4$
• B. $MgHC{O}_3$
• C. $NaCl$
• D. $MgC{l}_2$

Answer 1

Answer: (D)

Chlorides and sulphates of calcium and magnesium are responsible for permanent hardness of water.