A sparingly soluble salt MA has K_sp = 1.0 x 10^-10 and HA has K_a = 1.0 x 10^-5. In a buffer of fixed pH the solubility is S = sqrtK_sp(1 + [H+]/K_a) (neglect hydrolysis of M+). Select the correct statement(s).

At pH 7 the solubility is 1.0 x 10^-5 M

At pH 5 the solubility is 1.4 x 10^-5 M

The solubility at pH 2 is more than ten times that at pH 7

At pH 7 the solubility is 1.0 x 10^-5 M

At pH 5 the solubility is 1.4 x 10^-5 M

At pH 3 the solubility is 3.2 x 10^-4 M

The solubility at pH 2 is more than ten times that at pH 7

JEE Main levelOne or more correct optionsDifficulty 2 of 3ia084

A sparingly soluble salt $MA$ has $K_{s p} = 1.0 \times 1 0^{- 10}$ and $HA$ has $K_{a} = 1.0 \times 1 0^{- 5}$ . In a buffer of fixed pH the solubility is $S = K_{s p} (1 + [H X^{+}] / K_{a})$ (neglect hydrolysis of $M X^{+}$ ). Select the correct statement(s).

Using the formula: pH 7 gives

1.00 \times 1 0^{- 5} M

; pH 5 gives

1.41 \times 1 0^{- 5} M

; pH 3 gives

1.00 \times 1 0^{- 4} M

(not

3.2 \times 1 0^{- 4} M

); pH 2 gives

3.16 \times 1 0^{- 4} M

, i.e. 31.5 times the pH 7 value.