Answer:
In the first question;
Option D is correct answer i.e 2,3-dichlorobutyric acid is the most acidic and 3,4-dimethylbutyric acid is the least acidic.
In the second question;
Option A is the correct answer , 2,2-dibromopropionic acid is the most acidic and 3,3-bromopropionic acid is the least acidic.
Explanation:
The rate of acidity of carboxylic acid is affect by several factors.
For example;
Inductive effect is used to explain the acidity of carboxylic acids.
Acidity of carboxylic acid increase by withdrawing group (NO2,CN,X,ROH) and decreases by donating groups (OMe,NH2,alkyl group).
Halogen family group are highly electronegative and as such they increases the rate of acidity.
Also in naming organic compounds, we rank compounds with the least number of substituent attached to the organic compound.
In the first question, Option D is correct answer i.e 2,3-dichlorobutyric acid is the most acidic and 3,4-dimethylbutyric acid is the least acidic because 2,3-dichlorobutyric acid have the least number of substituent of chlorine atoms and chlorine atoms as well increases the rate of acidity.
Also, 3,4-dimethylbutyric acid is the least acidic because of attachment of methyl groups and higher number of substituent(methyl groups) attached to it.
In the second question:
Option A is the correct answer , 2,2-dibromopropionic acid is the most acidic and 3,3-bromopropionic acid is the least acidic because
Bromine (an halogen family atom) increase the rate of acidity and with decreasing the distance from COOH group, acidity increases. Also with increasing the distance from COOH group acidity decreases which makes Option A the correct answer.
