Question

Hard water when passed through ion - exchange resin containing RCOOH groups becomes free from:

• A. $C{l}^{-}$ions
• B. $S{O}_4^{2-}$ ions
• C. $H_3{O}^{+}$ions
• D. $C{a}^{2+}$ ions

Answer 1

The correct option is D $C{a}^{2+}$ ions

Hard water contains calcium and magnesium salt so when it is passed through negative ion exchange resin, it capture cations from water and make it free from $C{a}^{2+}$ ions.