Question

Name an alcohol and a carboxylic acid having two carbon atoms in their structures. Draw their structures and state how this alcohol can be converted into a carboxylic acid. What happens when these two compounds react in the presence of an acid? Write chemical equations for the reactions involved in the two cases mentioned above.

Hint:

Ethanol is oxidized to acetic acid in the presence of an oxidizing agent. In esterification, ethanol and acetic acid react with an acid catalyst to form an ester and water.

Answer 1

Let us consider ethanol (C\(_2\)H\(_5\)OH) as the alcohol and acetic acid (CH\(_3\)COOH) as the carboxylic acid. Both of these compounds contain two carbon atoms. - Ethanol (C\(_2\)H\(_5\)OH): Ethanol is a simple alcohol. Its structure is shown below: \[ \text{CH}_3\text{CH}_2\text{OH} \] - Acetic Acid (CH\(_3\)COOH):
Acetic acid is a carboxylic acid with two carbon atoms. Its structure is shown below: \[ \text{CH}_3\text{COOH} \] Conversion of Ethanol to Acetic Acid:
When ethanol is oxidized in the presence of an oxidizing agent like potassium dichromate (K\(_2\)Cr\(_2\)O\(_7\)) or oxygen (O\(_2\)), it is converted into acetic acid. \[ \text{CH}_3\text{CH}_2\text{OH} \xrightarrow{\text{Oxidizing Agent}} \text{CH}_3\text{COOH} \] Reaction Between Ethanol and Acetic Acid in Presence of Acid (Esterification): When ethanol and acetic acid react in the presence of an acid catalyst (such as sulfuric acid), they undergo an esterification reaction to form ethyl acetate and water. The reaction is as follows: \[ \text{CH}_3\text{CH}_2\text{OH} + \text{CH}_3\text{COOH} \xrightarrow{\text{H}^+} \text{CH}_3\text{COOCH}_2\text{CH}_3 + \text{H}_2\text{O} \] Here, ethyl acetate (CH\(_3\)COOCH\(_2\)CH\(_3\)) is the ester formed, and water is a byproduct.