An aromatic compound X with molecular formula `C_(9)H_(10)O` gives following chemical tests:
(i) Form 2,4-DNP derivative
(ii) Reduces Tollen's reagent
(iii) undergoes Cannizzaro's reaction
(iv) On vigorous oxidation 1, 2-Benzene dicarboxylic acid is obtained
The compound X is ,

Options

A.
B.
C.
D.

Explanation

To determine the structure of the aromatic compound X with the molecular formula C₉H₁₀O, we will analyze the given chemical tests step by step.

### Step 1: Analyze the Chemical Tests
1. **Formation of 2,4-DNP derivative**: This indicates that compound X contains a carbonyl group (C=O), which is characteristic of aldehydes and ketones.
2. **Reduces Tollen's reagent**: This test is specific for aldehydes, as only aldehydes can reduce Tollen's reagent to produce a silver mirror. This suggests that compound X is likely an aldehyde.
3. **Undergoes Cannizzaro's reaction**: Cannizzaro's reaction occurs in aldehydes that lack alpha-hydrogens. This means that compound X must be an aldehyde without alpha-hydrogens.
4. **On vigorous oxidation, 1,2-benzene dicarboxylic acid is obtained**: This indicates that the oxidation of compound X leads to the formation of a dicarboxylic acid, suggesting that compound X has substituents that can be oxidized to carboxylic acids.

### Step 2: Determine the Structure of Compound X
Given the information from the tests, we can deduce the structure of compound X.

- Since it is an aromatic compound with a carbonyl group and no alpha-hydrogens, it is likely to be an aromatic aldehyde.
- The oxidation leading to 1,2-benzene dicarboxylic acid suggests that the structure has substituents that can be oxidized.

A suitable candidate for compound X is **2-ethylbenzaldehyde** (or **o-ethylbenzaldehyde**), which has the following structure:

```
CHO
|
C6H4 - CH2 - CH3
```

### Step 3: Verify the Molecular Formula
- Count the number of carbon atoms:
- Benzene ring contributes 6 carbons.
- Ethyl group contributes 2 carbons.
- Aldehyde contributes 1 carbon.
- Total = 6 + 2 + 1 = 9 carbons (C₉).

- Count the number of hydrogen atoms:
- The benzene ring contributes 4 hydrogens (due to substitution).
- The ethyl group contributes 5 hydrogens.
- The aldehyde contributes 1 hydrogen.
- Total = 4 + 5 + 1 = 10 hydrogens (H₁₀).

- There is 1 oxygen from the aldehyde group (O).

Thus, the molecular formula is confirmed as C₉H₁₀O.

### Conclusion
The compound X is **2-ethylbenzaldehyde**.

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