The ionization constant of $HF$, $HCOOH$ and $HCN$ at $298\, K$ are $6.8 \times 10^{-4}, 1.8 \times 10^{-4}$ and $4.8 \times 10^{-9}$ respectively. Calculate the ionization constants of the corresponding conjugate base.
The ionization constant of $HF$, $HCOOH$ and $HCN$ at $298\, K$ are $6.8 \times 10^{-4}, 1.8 \times 10^{-4}$ and $4.8 \times 10^{-9}$ respectively. Calculate the ionization constants of the corresponding conjugate base.
It is known that,
$K_{b}=\frac{K_{w}}{K_{a}}$
Given $K_{a}$ of $HF =6.8 \times 10^{-4}$
Hence, $K_{b}$ of its conjugate base $F^{-}$
$=\frac{K_{w}}{K_{a}}$
$=\frac{10^{-14}}{6.8 \times 10^{-4}}$
$=1.5 \times 10^{-11}$
Given,
$K_{a}$ of $HCOOH =1.8 \times 10^{-4}$
Hence, $K_{b}$ of its conjugate base $HCOO ^{-}$
$=\frac{K_{w}}{K_{a}}$
$=\frac{10^{-14}}{1.8 \times 10^{-4}}$
$=5.6 \times 10^{-11}$
Given,
$K_{a}$ of $HCN =4.8 \times 10^{-9}$
Hence, $K_{b}$ of its conjugate base $CN ^{-}$
$=\frac{K_{w}}{K_{a}}$
$=\frac{10^{-14}}{4.8 \times 10^{-9}}$
$=2.08 \times 10^{-6}$
Similar Questions
Find $pH$ of $5 \times 10^{-3}\, M$ $H_2CO_3$ solution having $10\%$ dissociation
Find $pH$ of $5 \times 10^{-3}\, M$ $H_2CO_3$ solution having $10\%$ dissociation
The ionization constant of propanoic acid is $1.32 \times 10^{-5}$. Calculate the degree of ionization of the acid in its $0.05\, M$ solution and also its $pH$. What will be its degree of ionization if the solution is $0.01$ $M$ in $HCl$ also?
The ionization constant of propanoic acid is $1.32 \times 10^{-5}$. Calculate the degree of ionization of the acid in its $0.05\, M$ solution and also its $pH$. What will be its degree of ionization if the solution is $0.01$ $M$ in $HCl$ also?
The hydrogen ion concentration of a $0.006\,M$ benzoic acid solution is $({K_a} = 6 \times {10^{ - 5}})$
The hydrogen ion concentration of a $0.006\,M$ benzoic acid solution is $({K_a} = 6 \times {10^{ - 5}})$
What is the percent ionization $(\alpha)$ of a $0.01\, M\, HA$ solution ? .......$\%$ $(K_a = 10^{-6})$
What is the percent ionization $(\alpha)$ of a $0.01\, M\, HA$ solution ? .......$\%$ $(K_a = 10^{-6})$
What is the $pH$ of $0.001 \,M$ aniline solution? The ionization constant of aniline can be taken from Table . Calculate the degree of ionization of aniline in the solution. Also calculate the ionization constant of the conjugate acid of aniline.
Base
$K _{ b }$
Dimethylamine, $\left( CH _{3}\right)_{2} NH$
$5.4 \times 10^{-4}$
Triethylamine, $\left( C _{2} H _{5}\right)_{3} N$
$6.45 \times 10^{-5}$
Ammonia, $NH _{3}$ or $NH _{4} OH$
$1.77 \times 10^{-5}$
Quinine, ( $A$ plant product)
$1.10 \times 10^{-6}$
Pyridine, $C _{5} H _{5} N$
$1.77 \times 10^{-9}$
Aniline, $C _{6} H _{5} NH _{2}$
$4.27 \times 10^{-10}$
Urea, $CO \left( NH _{2}\right)_{2}$
$1.3 \times 10^{-14}$
What is the $pH$ of $0.001 \,M$ aniline solution? The ionization constant of aniline can be taken from Table . Calculate the degree of ionization of aniline in the solution. Also calculate the ionization constant of the conjugate acid of aniline.
| Base | $K _{ b }$ |
| Dimethylamine, $\left( CH _{3}\right)_{2} NH$ | $5.4 \times 10^{-4}$ |
| Triethylamine, $\left( C _{2} H _{5}\right)_{3} N$ | $6.45 \times 10^{-5}$ |
| Ammonia, $NH _{3}$ or $NH _{4} OH$ | $1.77 \times 10^{-5}$ |
| Quinine, ( $A$ plant product) | $1.10 \times 10^{-6}$ |
| Pyridine, $C _{5} H _{5} N$ | $1.77 \times 10^{-9}$ |
| Aniline, $C _{6} H _{5} NH _{2}$ | $4.27 \times 10^{-10}$ |
| Urea, $CO \left( NH _{2}\right)_{2}$ | $1.3 \times 10^{-14}$ |