What is the Difference Between Carboxylic Acid and Ester?

Carboxylic acids and esters are both organic compounds that contain a carbonyl group (C=O), but they differ in the nature of the substituents attached to the carbonyl carbon atom. Here are the key differences between carboxylic acids and esters:

1. Functional Group: In a carboxylic acid, the carbonyl carbon atom bonds to a hydroxyl group (−OH), forming the carboxyl functional group (R−CO2H). In an ester, the carbonyl carbon atom bonds to an alkoxy group such as −OCH3, forming an ester functional group (R−CO2R').
2. Hydrogen Bonding: Carboxylic acids exhibit hydrogen bonding between molecules due to the hydrogen atom in the carboxyl group. Esters do not have hydrogen bonds between molecules, which results in lower vapor pressures than carboxylic acids.
3. Acidity: Carboxylic acids are weak organic acids, while esters are not acids.
4. Naming: Carboxylic acids have a general formula of R−CO2H, where R represents an organic group. Esters have a general formula of R−CO2R', where R and R' represent organic groups.

In summary, carboxylic acids have a carboxyl functional group with a hydroxyl group attached to the carbonyl carbon atom, exhibit hydrogen bonding, and show weak acidity. In contrast, esters have an ester functional group with an alkoxy group attached to the carbonyl carbon atom, do not exhibit hydrogen bonding, and do not show acidity.

Comparative Table: Carboxylic Acid vs Ester

Carboxylic acids and esters are both organic compounds that contain a carbonyl group, but they have different functional groups and properties. Here is a table summarizing the differences between them:

Carboxylic acids have a carboxyl group (R-COOH), where the oxygen atom is bonded to a hydrogen atom and a carbon atom. Esters, on the other hand, have an esters group (R-COO-R'), where the oxygen atom is bonded to two carbon atoms. Carboxylic acids have hydrogen bonding between molecules, while esters do not. Carboxylic acids have higher vapor pressures compared to esters, which have lower vapor pressures than the alcohols and carboxylic acids from which they are derived. Carboxylic acids often have strong odors, such as vinegar, while esters often have pleasant odors and flavors, like ripe bananas. Esters are produced by the reaction of carboxylic acids with alcohols.