Rank the following ions in the order of increasing basicity:

a.${\mathbf{\text{CH}}}_{\mathbf{\text{3}}}\stackrel{\mathbf{-}}{\mathbf{\text{C}}}{\mathbf{\text{H}}}_{\mathbf{\text{2}}}{\mathbf{\text{,CH}}}_{\mathbf{\text{3}}}{\mathbf{\text{O}}}^{\mathbf{-}}{\mathbf{\text{,CH}}}_{\mathbf{\text{3}}}\stackrel{\mathbf{-}}{\mathbf{\text{N}}}\mathbf{\text{H}}$

b.${\mathbf{\text{CH}}}_{\mathbf{3}}^{\mathbf{-}}{\mathbf{\text{,HO}}}^{\mathbf{\text{–}}}{\mathbf{\text{,Br}}}^{\mathbf{\text{–}}}$

c.

d.

Basicityindicates the capability of a base to receive a proton. It can be linked with the ${\mathbf{pK}}_{\mathbf{a}}$ value of the particular conjugate acid.

a. The strongest acid will possess the weakest conjugate base. The increasing acidity of conjugate acids is shown below

${\text{CH}}_{\text{3}}{\text{CH}}_3{\text{<CH}}_{\text{3}}{\text{NH}}_2\text{<}{\text{CH}}_{\text{3}}\text{OH}$

The ions in the order of increasing basicity are shown as follows:

${\text{CH}}_{\text{3}}{\text{O}}^{-}{\text{<CH}}_{\text{3}}\stackrel{-}{\text{N}}\text{H<}{\text{CH}}_{\text{3}}\stackrel{-}{\text{C}}{\text{H}}_{\text{2}}$

b. The highly strong acid will have a weak conjugate base. The increasing acidity of conjugate acids can be given below

${\text{CH}}_4{\text{<H}}_2\text{O<HBr}$

The ions in the order of increasing basicity are shown as follows:

${\text{Br}}^{\text{–}}{\text{<HO}}^{\text{–}}{\text{<CH}}_3^{-}$

c. Strong acids are regarded to possess a weak conjugate base. The increasing acidity of the conjugate acids can be given below:

${\mathrm{CH}}_3{\text{CH}}_2\mathrm{OH}{\text{<CH}}_3{\text{COOH<ClCH}}_2\mathrm{COOH}$

The ions in the order of increasing basicity are shown below:

${\text{ClCH}}_2{\text{COO}}^{-}{\text{<CH}}_3{\text{COO}}^{-}{\text{<CH}}_3{\text{CH}}_2{\text{O}}^{-}$

d. The conjugate base of a strong acid is considered to be weak. The increasing acidity of the conjugate acid is shown below:

Acidity order of conjugate acids

The ions in the order of increasing basicity are shown below:

Basicity order of the compounds