Which of the following can reduce Benedict's solution?

Options

A. a.Ethanoic acid
B. b.Methanoic acid
C. c.Phenyl methanal
D. d.Methanal

Explanation

To determine which of the given compounds can reduce Benedict's solution, we need to analyze each option based on their chemical properties and the nature of Benedict's reagent.

### Step-by-Step Solution:

1. **Understanding Benedict's Solution**:
- Benedict's solution is a chemical reagent that contains copper(II) sulfate (CuSO4·5H2O), sodium carbonate (Na2CO3), and sodium citrate (Na3C6H5O7).
- It is used to test for reducing sugars and aldehydes, where the copper(II) ions (Cu²⁺) in the solution can be reduced to copper(I) oxide (Cu2O), which precipitates as a brick-red solid.

2. **Identifying the Options**:
- The options provided are:
- A) Ethanoic acid (acetic acid)
- B) Methanoic acid (formic acid)
- C) Phenylmethanol (benzyl alcohol)
- D) Methanol (methyl alcohol)

3. **Analyzing Each Compound**:
- **A) Ethanoic acid (CH3COOH)**:
- Ethanoic acid is a carboxylic acid and does not have the ability to reduce Benedict's solution since it cannot be oxidized to carbon dioxide by it.
- **B) Methanoic acid (HCOOH)**:
- Methanoic acid is also known as formic acid. It can reduce Benedict's solution because it can be oxidized to carbon dioxide (CO2), thus reducing the Cu²⁺ ions to Cu2O.
- **C) Phenylmethanol (C6H5CH2OH)**:
- Phenylmethanol is an alcohol and does not contain an aldehyde group. It cannot reduce Benedict's solution as it does not undergo oxidation to form an aldehyde or a carboxylic acid.
- **D) Methanol (CH3OH)**:
- Methanol is also an alcohol. However, it can be oxidized to formaldehyde (an aldehyde), which can then reduce Benedict's solution. Therefore, methanol can indirectly reduce the solution.

4. **Conclusion**:
- The compounds that can reduce Benedict's solution are:
- B) Methanoic acid (formic acid)
- D) Methanol (as it can be oxidized to formaldehyde, which can reduce the solution).

### Final Answer:
- **Methanoic acid (B) and Methanol (D)** can reduce Benedict's solution.