Which organic compound can reduces Tollen's reagent ?

Options

A. Oxalic acid
B. Citric acid
C. Acetic acid
D. Formic acid

Answer

To determine which organic compound can reduce Tollen's reagent, we need to identify the presence of an aldehyde functional group in the given options. Tollen's reagent is used to test for aldehydes and certain other compounds.

### Step-by-Step Solution:

1. **Understand Tollen's Reagent**: Tollen's reagent is a solution of silver nitrate (AgNO3) in ammonia (NH3). It is used to detect the presence of aldehydes, which can reduce the silver ion (Ag+) to metallic silver (Ag).

2. **Evaluate the Options**:
- **Option 1: Oxalic Acid**
- Structure: HOOC-COOH
- Analysis: Oxalic acid does not contain an aldehyde group (–CHO). Therefore, it cannot reduce Tollen's reagent.

- **Option 2: Citric Acid**
- Structure: C6H8O7 (contains multiple carboxylic groups and hydroxyl groups)
- Analysis: Citric acid also does not contain an aldehyde group. Hence, it cannot reduce Tollen's reagent.

- **Option 3: Acetic Acid**
- Structure: CH3COOH
- Analysis: Acetic acid does not have an aldehyde group. Thus, it cannot reduce Tollen's reagent.

- **Option 4: Formic Acid**
- Structure: HCOOH
- Analysis: Formic acid contains the aldehyde group (–CHO). Therefore, it can reduce Tollen's reagent.

3. **Conclusion**: The only compound among the options that can reduce Tollen's reagent is **Formic Acid**.

### Final Answer: Formic Acid

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