The molecular formula of a commercial resin used for exchanging ions in water softening is C 8 H 7 SO 3- Na + (mol. wt 206). What would be the maximum uptake of Ca 2+ ions by the resin when expressed in mole per gram resin?

Question

The molecular formula of a commercial resin used for exchanging ions in water softening is C 8 H 7 SO 3- Na + (mol. wt 206). What would be the maximum uptake of Ca 2+ ions by the resin when expressed in mole per gram resin? (A) (1/103) (B) (1/206) (C) (2/309) (D) (1/412)

Tardigrade Admin · Accepted Answer

underset2 mole2 C 8 H 7 SO 3- Na ++ underset1 mole Ca 2+ longrightarrow underset(2 × 206=412 g)( C 8 H 7 SO 3)2 Ca +2 Na + 412 g of resin take up Ca 2+ ions =1 mole ∴ 1 g of resin will take up Ca 2+=(1/412) mole

Q. The molecular formula of a commercial resin used for exchanging ions in water softening is $C_{8} H_{7} S O_{3}^{-} N a^{+}$ (mol. wt 206). What would be the maximum uptake of $C a^{2 +}$ ions by the resin when expressed in mole per gram resin?

$\frac{1}{103}$

$\frac{1}{206}$

$\frac{2}{309}$

$\frac{1}{412}$

$2 m o l e 2 C_{8} H_{7} S O_{3}^{-} N a^{+} + 1 m o l e C a^{2 +} ⟶ (2 \times 206 = 412 g) (C_{8} H_{7} S O_{3})_{2} C a + 2 N a^{+}$

$412 g$ of resin take up $C a^{2 +}$ ions $= 1 m o l e$

$∴ 1 g$ of resin will take up $C a^{2 +} = \frac{1}{412}$ mole

Q. The molecular formula of a commercial resin used for exchanging ions in water softening is C8​H7​SO3−​Na+ (mol. wt 206). What would be the maximum uptake of Ca2+ ions by the resin when expressed in mole per gram resin?

1031​

2061​

3092​

4121​