Ionic Equilibrium · Chemistry · VITEEE

What is the degree of dissociation of $$0.05 \mathrm{~M~NH}_3$$ if its $$\mathrm{pK}{ }_a$$ is 4.75 and $$\mathrm{pH}$$ is 11 ?

The $$[\mathrm{OH}]^{-}$$ in a solution is $$1 \mathrm{~mol} \mathrm{~L}^{-1}$$. The $$\mathrm{pH}$$ of the solution is

The solubility of $$\mathrm{Fe}(\mathrm{OH})_3$$ is $$x \mathrm{~mol} \mathrm{~L}^{-1}$$. Its $$K_{\mathrm{sp}}$$ would be