PASSAGE-IV : A neutral organic compound A of molecular formula `C_(2)H_(6)O`, on oxidation with potassium dichromate and sulphuric acid gives an acidic compound B. The compound A reacts with B on warming in presence of conc. `H_(2)SO_(4)` to give a sweet smelling substance C. C on heating with D gives back A.
In the above sequence of reactions compound B is

Options

A. ethanol
B. ethanoic acid
C. ethyl ethanoate
D. water

Explanation

To determine the compound B in the given sequence of reactions, we will analyze the information step by step.

### Step-by-Step Solution:

1. **Identify Compound A**:
- The molecular formula of compound A is C₂H₆O.
- This formula corresponds to an alcohol, specifically ethanol (C₂H₅OH).

2. **Oxidation of Compound A**:
- When ethanol (A) is oxidized using potassium dichromate (K₂Cr₂O₇) in the presence of sulfuric acid (H₂SO₄), it forms an acidic compound.
- The oxidation of ethanol leads to the formation of acetic acid (ethanoic acid), which has the formula CH₃COOH.

3. **Identify Compound B**:
- From the oxidation of ethanol, the acidic compound B is identified as acetic acid (CH₃COOH).

4. **Reaction of A with B**:
- When ethanol (A) reacts with acetic acid (B) in the presence of concentrated sulfuric acid and is warmed, an ester is formed.
- The reaction produces ethyl acetate (C), which is a sweet-smelling compound.

5. **Formation of Compound C**:
- The sweet-smelling substance C is ethyl acetate (CH₃COOC₂H₅).

6. **Heating C with D**:
- When ethyl acetate (C) is heated with a compound D, which is sodium hydroxide (NaOH), hydrolysis occurs, leading to the regeneration of ethanol (A) and sodium acetate.

### Conclusion:
- Therefore, the compound B in the above sequence of reactions is **acetic acid (ethanoic acid)**, which is represented by the formula CH₃COOH.