C_{6}H_{5}OH **⇌** C_{6}H_{5}O^{–} + H^{+}

Initial 0.05M 0 0

After dissociation 0.05-x , x, x

\( K_{}\alpha = \dfrac{x^{2}}{0.05-x} \)

Because the value of the ionization constant is very small, the value of x is very small. Accordingly, w e may ignore x in the denominator.

\( x = \sqrt{1\times 10^{-10}\times 0.05} \)

x =

x = 2.2×10^{-6}M

In presence of 0.01 sodium phenolate(C_{6}H_{5}Na), suppose y is the amount of phenol dissociated, then at equilibrium

[C_{6}H_{5}OH] = 0.05 -y

[C_{6}H_{5}OH] ≈ 0.05

[C_{6}H_{5}O^{–}] = 0.01 + y ≈ 0.01M,

[H^{+}]=yM

\( K_{\alpha }=\dfrac{(0.01)(y)}{0.05} \)

\( =1.0\times 10^{-10}\)

y = 5 × 10^{-10}

\( \alpha = \dfrac{y}{c}α= \dfrac{5\times 10^{-10}}{5\times 10^{-2}} \)

α = 10^{-8}

The concentration of sulphide ion in 0.1M HCl solution saturated with hydrogen sulphide is 1.0 × 10^{–19} M. If 10 mL of this is added to 5 mL of 0.04M solution of the following: FeSO_{4}, MnCl_{2}, ZnCl_{2} and CdCl_{2} . in which of these solutions precipitation will take place?

What is the minimum volume of water required to dissolve 1g of calcium sulphate at 298 K? (For calcium sulphate, K_{sp} is 9.1 × 10^{–6}).

What is the maximum concentration of equimolar solutions of ferrous sulphate and sodium sulphide so that when mixed in equal volumes, there is no precipitation of iron sulphide? (For iron sulphide, Ksp = 6.3 × 10^{–18}).

The ionization constant of benzoic acid is 6.46 × 10^{–5} and Ksp for silver benzoate is 2.5 × 10^{–13}. How many times is silver benzoate more soluble in a buffer of pH 3.19 compared to its solubility in pure water?

Equal volumes of 0.002 M solutions of sodium iodate and cupric chlorate are mixed together. Will it lead to precipitation of copper iodate? (For cupric iodate K_{sp} = 7.4 × 10^{–8} ).