Question

The increasing order of base strength of \[C{l^ - }C{H_3}CO{O^ - }\], \[^ - OH\] and \[{F^ - }\] is
\[A.\,\,C{l^ - }\, < \,{F^ - }\, < \,C{H_3}CO{O^ - }\, < O{H^ - }\]
\[B.\,\,C{l^ - }\, > \,{F^ - }\, > \,C{H_3}CO{O^ - }\, > O{H^ - }\]
\[C.\,\,C{H_3}CO{O^ - }\, < \,C{l^ - }\, < \,\,{F^ - }\, < O{H^ - }\]
\[D.\,\,None\,\,of\,these\]

Answer 1

Hint: Acids does the proton donation and base accepts the proton. The primary strength of any type is its ability to accept \[{H^ + }\] of another type. The greater the type's ability to accept \[{H^ + }\] of another species, the greater its fundamental strength. Organic chemists usually compare the strength of bases using the forces of their conjugate acids, measured in pKa. Example: Base strengths of \[{F^ - }\] and \[H{S^ - }\].

Complete step-by-step answer:
Conjugate acid of \[{F^ - }\, = \,\,{F^ - }\, + \,\,{H^ + }\, = \,\,HF\]
\[pKa{\text{ }}of{\text{ }}HF{\text{ }} = {\text{ }}3.17\]
Conjugate acid of \[H{S^ - }\, = \,\,H{S^ - }\, + \,\,{H^ + }\, = \,\,{H_2}S\]
\[pKa{\text{ }}of{\text{ }}{H_2}S{\text{ }} = {\text{ }}7.00\]
In this, the \[HF\] is a stronger acid than \[{H_2}S\]. As there is the stronger acid, the weaker the conjugate base, and vice versa. Therefore, \[H{S^ - }\] is a stronger base than \[{F^ - }\] .
The strong acid is a weak conjugate base and the strong base is a weak conjugate acid.

In the given options let's add the \[{H^ + }\] so that we can get the conjugate acid and let’s arrange in the increasing order of acidic strength.
\[{H_2}O{\text{ }} < {\text{ }}C{H_3}COOH{\text{ }} < {\text{ }}HF{\text{ }} < {\text{ }}HCl\]
If we write the acidic strength in the opposite, it becomes the basic strength.
\[O{H^ - } > {\text{ }}C{H_3}CO{O^ - } > {\text{ }}{F^ - } > {\text{ }}C{l^ - }\]
So, the basic strength in the given option is;
\[A.\,\,C{l^ - }\, < \,{F^ - }\, < \,C{H_3}CO{O^ - }\, < O{H^ - }\]

So, the correct answer is option A.

Note: Not all acids and bases ionize or dissociate to the same extent. This leads to the assertion that acids and bases are not all of the equal strength to produce \[{H^ + }\] and \[O{H^ - }\] ions in solution. The terms "strong" and "weak" indicate the strength of an acid or a base. The terms strong and weak describe the ability of acidic and basic solutions to conduct electricity. If the acid or base strongly conducts electricity, it is a strong acid or base. When there is weak acid or base it conducts electricity weakly.