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Q. The molecular formula of a commercial resin used for exchanging ions in water softening is $C_8{H}_{7}S{O}_{3}Na(Mol.Wt.206gmo{l}^{-1})$ .What would be the maximum uptake of $C{a}^{2+}$ ions by the resin when expressed in mole per gram resin?

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Q. The molecular formula of a commercial resin used for exchanging ions in water softening is $C_8{H}_{7}S{O}_{3}Na$ $($molecular weight $206)$. What would be the maximum uptake of $C{a}^{2+}$ ions by the resin when expressed in mole per gram resin?

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Q. The empirical formula of a commercial ion exchange resin is $C_8{H}_{7}S{O}_{3}Na(M.M=206)$. The resin can be used to soften water according to the reaction:
$C{a}^{2+}+2C_8{H}_{7}S{O}_{3}Na\to Ca(C_8{H}_{7}S{O}_3{)}_2+2N{a}^{+}$
What would be the maximum uptake of $C{a}^{2+}$ by the resin expressed in $\text{mol/g}$ of resin?