At 25 ^circ C,a weak acid HX has the dissoci | vedclass

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(B) The salt $NaX$ is formed from a weak acid $(HX)$ and a strong base $(NaOH)$.For such a salt,the hydrolysis constant $K_h$ is given by $K_h = \frac

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$0.01$

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(B) The salt $NaX$ is formed from a weak acid $(HX)$ and a strong base $(NaOH)$.For such a salt,the hydrolysis constant $K_h$ is given by $K_h = \frac{K_w}{K_a}$.Given $K_w = 10^{-14}$ and $K_a = 10^{-5}$,we have $K_h = \frac{10^{-14}}{10^{-5}} = 10^{-9}$.The formula for the degree of hydrolysis $(h)$ for a salt of a weak acid and strong base is $h = \sqrt{\frac{K_h}{C}}$.Here,$C = 0.1 \ M = 10^{-1} \ M$.$h = \sqrt{\frac{10^{-9}}{10^{-1}}} = \sqrt{10^{-8}} = 10^{-4}$.The percentage of hydrolysis is $h 	imes 100 = 10^{-4} 	imes 100 = 0.01 \%$.

At $25 \ ^\circ C$,a weak acid $HX$ has the dissociation constant $K_a = 1 \times 10^{-5}$. It forms a salt $NaX$ on reaction with an alkali. The percentage of degree of hydrolysis of a $0.1 \ M$ solution of $NaX$ is $..... \%$.

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