Question

The ion exchange resin which remove metal ions from hard water consist of giant organic molecule containing :

• A. $-Cl$ group
• B. $-COOH$ group
• C. $-OH$ group
• D. $-N{H}_2$ group

Answer 1

Answer: (B)

$-COOH$ group

Giant organic molecules having acidic or basic groups are known as ion-exchange resins. Acid resins contain the acid group $(-COOH)$.

Acid resins exchange their $H^{+}$ ions with other cations such as $C{a}^{2+},M{g}^{2+}$ etc., present in hard water. Therefore, acid resins are known as base-exchange resins.

Hence, option B is correct.