Reddish brown colouration when neutral `FeCl_(3)` is added to the `CH_(3)CO O^(Θ)` aq solution is due to the formation of (a) ____.

Answer

To solve the question regarding the reddish brown coloration when neutral ferric chloride (FeCl₃) is added to an aqueous solution of acetate ions (CH₃COO⁻), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants in this case are neutral ferric chloride (FeCl₃) and acetate ions (CH₃COO⁻) in an aqueous solution.

2. **Understand the Reaction**:
- When FeCl₃ is added to an acetate ion solution, the ferric ions (Fe³⁺) from FeCl₃ interact with the acetate ions (CH₃COO⁻).

3. **Formation of Complex**:
- The ferric ions can form a complex with acetate ions. The reaction can be represented as:
\[ \text{Fe}^{3+} + 6 \text{CH}_3\text{COO}^- \rightarrow \text{Fe(CH}_3\text{COO)}_6^{3-} \]
- This complex is known as ferric acetate.

4. **Color Observation**:
- The complex formed, specifically \(\text{Fe(OH)}_2(\text{CH}_3\text{COO})_6^{+}\), gives a reddish-brown coloration. This is characteristic of ferric compounds.

5. **Conclusion**:
- Therefore, the reddish brown coloration when neutral FeCl₃ is added to CH₃COO⁻ aqueous solution is due to the formation of the complex \(\text{Fe(OH)}_2(\text{CH}_3\text{COO})_6^{+}\).

### Final Answer:
The reddish brown coloration when neutral FeCl₃ is added to CH₃COO⁻ aqueous solution is due to the formation of \(\text{Fe(OH)}_2(\text{CH}_3\text{COO})_6^{+}\).

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