Arrange the following compounds in increasing | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) The $pK_{a}$ value is inversely proportional to the acidity of the compound. Stronger acids have lower $pK_{a}$ values.$1$. $p$-nitrobenzoic acid

Vedclass · Accepted Answer

$C < B < D < A$

Vedclass · Answer

(A) The $pK_{a}$ value is inversely proportional to the acidity of the compound. Stronger acids have lower $pK_{a}$ values.$1$. $p$-nitrobenzoic acid $(A)$: The $-NO_2$ group is a strong electron-withdrawing group ($-I$ and $-M$ effect),which significantly increases the acidity of the carboxylic acid group.$2$. Benzoic acid $(D)$: This is the reference compound.$3$. $p$-methoxybenzoic acid $(B)$: The $-OCH_3$ group is an electron-donating group ($+M$ effect),which decreases the acidity of the carboxylic acid group compared to benzoic acid.$4$. $p$-nitrophenol $(C)$: Phenols are generally much weaker acids than carboxylic acids. Although the $-NO_2$ group increases the acidity of phenol,it is still significantly less acidic than the carboxylic acids listed above.Comparing the acidity: $p$-nitrobenzoic acid $(A)$ > benzoic acid $(D)$ > $p$-methoxybenzoic acid $(B)$ > $p$-nitrophenol $(C)$.Therefore,the increasing order of $pK_{a}$ values is: $C < B < D < A$.

Arrange the following compounds in increasing order of their $pK_{a}$ values:
$(a)$ $p$-nitrobenzoic acid
$(b)$ $p$-methoxybenzoic acid
$(c)$ $p$-nitrophenol
$(d)$ benzoic acid

Similar Questions

An aryl carboxylic acid on treatment with sodium hydrogen carbonate liberates a gaseous molecule. Identify the gas molecule liberated.

Which of the following compounds has the maximum acidic strength?

Which is the strongest acid?

Which of the following orders of relative strengths of acids is correct?

Assertion $(A)$: Carboxylic acids are more acidic than Phenols.
Reason $(R)$: Resonance structures of carboxylate ion are equivalent,while resonance structures of phenoxide ion are not equivalent.

Vedclass Test Series

Exam Paper Generator

Online Exam Module

Arrange the following compounds in increasing order of their $pK_{a}$ values:$(a)$ $p$-nitrobenzoic acid$(b)$ $p$-methoxybenzoic acid$(c)$ $p$-nitrophenol$(d)$ benzoic acid