Write characteristic and uses of weak base equilibrium constant ${K_b}$.

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$(i)$ If the value of $K_{b}$ is more than base is more strong. $(ii)$ $K_{b}$ is a dimensionless quantity.

$(iii)$ With the help of $\mathrm{K}_{b}$, calculate $\left[\mathrm{OH}^{-}\right]$of weak base and then $pOH.$ $(iv)$ The ionization degree $(\alpha)$ of base can be calculated by value of $K_{b}$.

$(v)$ $\mathrm{pK}_{b}$ is calculate by using the value of $\mathrm{K}_{b^{*}}$

$\mathrm{pK}_{b}=-\log \left(\mathrm{K}_{b}\right)$

If $\mathrm{pK}_{b}$ value is more then base is less strong.

$\mathrm{K}_{b}$ $1 \times 10^{-1}$ $1 \times 10^{-2}$ $1 \times 10^{-3}$
$\mathrm{pK}_{b}$ $+1$ $+2$ $+3$

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