Question

Identify the products of following reaction :
$$\text{C}_6\text{H}_5\text{COOC}_2\text{H}_5 \xrightarrow[\Delta]{\text{dil. H}_2\text{SO}_4} \dots$$

• A. $\text{C}_6\text{H}_5\text{OH} + \text{C}_2\text{H}_5\text{OH}$
• B. $\text{C}_6\text{H}_5\text{COOH} + \text{C}_2\text{H}_5\text{COOH}$
• C. $\text{C}_6\text{H}_5\text{COOH} + \text{C}_2\text{H}_5\text{OH}$
• D. $\text{C}_6\text{H}_5\text{OH} + \text{C}_2\text{H}_5\text{COOH}$

Hint:

To easily predict ester hydrolysis products, simply split the single covalent bond connecting the carbonyl carbon to the oxygen atom (C-O). Give an $-\text{OH}$ group to the carbonyl side to build the acid, and add a hydrogen atom $-\text{H}$ to the oxygen side to complete the alcohol!

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
The problem presents an organic reaction where ethyl benzoate ($\text{C}_6\text{H}_5\text{COOC}_2\text{H}_5$) is heated with dilute sulfuric acid ($\text{dil. H}_2\text{SO}_4$). We need to determine the chemical structures of the products formed.

Step 2: Key Formula or Approach:
Heating an ester with a dilute aqueous mineral acid leads to acid-catalyzed ester hydrolysis. This reaction cleaves the ester linkage to regenerate the parent carboxylic acid and alcohol:
$$\text{R-COOR}' + \text{H}_2\text{O} \xrightarrow{\text{H}^+} \text{R-COOH} + \text{R}'\text{-OH}$$

Step 3: Detailed Explanation:
Let's look at the given ester, ethyl benzoate ($\text{C}_6\text{H}_5\text{COOC}_2\text{H}_5$):
The acyl group (R-CO-) corresponds to the benzoic acid fragment ($\text{C}_6\text{H}_5\text{CO-}$).
The alkoxy group ($-\text{OR}'$) corresponds to the ethoxy fragment ($-\text{OC}_2\text{H}_5$).
When water molecules attack the carbonyl carbon under acidic conditions, the chemical bonds cleave such that:
1. The $\text{C}_6\text{H}_5\text{CO-}$ portion joins with a hydroxyl group ($-\text{OH}$) to yield benzoic acid ($\text{C}_6\text{H}_5\text{COOH}$).
2. The $-\text{C}_2\text{H}_5$ portion captures a hydrogen atom ($-\text{H}$) to yield ethyl alcohol ($\text{C}_2\text{H}_5\text{OH}$).
The total balanced reaction equation is:
$$\text{C}_6\text{H}_5\text{COOC}_2\text{H}_5 + \text{H}_2\text{O} \xrightarrow[\Delta]{\text{dil. H}_2\text{SO}_4} \text{C}_6\text{H}_5\text{COOH} + \text{C}_2\text{H}_5\text{OH}$$ This matches option (C).

Step 4: Final Answer:
The products are benzoic acid and ethanol ($\text{C}_6\text{H}_5\text{COOH} + \text{C}_2\text{H}_5\text{OH}$), which corresponds to option (C).