Question

Which of the following is not a disadvantage of using hard water?

Answer 1

In an ion exchange using hard water is not a disadvantage since it becomes soft by exchanging anions or cations. $N{a}^{+}$, $C{a}^{2+}$ and $M{g}^{2+}$ ions (from water) are exchanged with $H^{+}$ ions (from cation exchange resins). $C{l}^{-}$, $S{O}_4^{2-}$ and $N{O}_3^{-}$ ions (from water) are exchanged with $O{H}^{-}$ ions (from anion exchange resins).