Benzaldehyde can be oxidised to corresponding carboxylate anion with

Options

A. Fehling's reagent
B. Tollen's reagent
C. Both Fehling's and Tollen's reagent
D. Neither Fehling's nor Tollen's reagent

Answer

To solve the question "Benzaldehyde can be oxidised to corresponding carboxylate anion with," we need to analyze the oxidation reactions of benzaldehyde with the reagents mentioned: Tollens reagent and Fehling's solution.

### Step-by-Step Solution:

1. **Identify the Structure of Benzaldehyde**:
- Benzaldehyde has the formula C6H5CHO, where the functional group is an aldehyde (-CHO).

2. **Understand the Oxidation Process**:
- Oxidation of benzaldehyde involves converting the aldehyde group (-CHO) into a carboxylate anion (-COO⁻).

3. **Examine Tollens Reagent**:
- Tollens reagent is a solution of silver nitrate (AgNO3) in ammonia (NH3). It is used to oxidize aldehydes to carboxylic acids.
- The reaction can be represented as:
\[ \text{RCHO} + \text{Tollens reagent} \rightarrow \text{RCOO}^- + 2\text{Ag} + 4\text{NH}_3 + 2\text{H}_2\text{O} \]
- This shows that benzaldehyde can be oxidized to the corresponding carboxylate anion using Tollens reagent.

4. **Examine Fehling's Solution**:
- Fehling's solution contains copper(II) ions (Cu²⁺) in alkaline solution. It is also used to oxidize aldehydes.
- The reaction can be represented as:
\[ \text{RCHO} + \text{Fehling's solution} \rightarrow \text{RCOO}^- + \text{Cu}_2\text{O} + 3\text{H}_2\text{O} \]
- This indicates that Fehling's solution can also oxidize benzaldehyde to the corresponding carboxylate anion.

5. **Conclusion**:
- Since both Tollens reagent and Fehling's solution can oxidize benzaldehyde to the corresponding carboxylate anion, the correct answer to the question is:
- **Option 3: Both Fehling's and Tollens reagent.**