Ferric hydroxide sol is prepared by

Options

A. treating ferric chloride with dilute sodium hydroxide solution
B. treating ferric chloride with dilute ammonium hydroxide solution
C. adding ferric chloride solution to boiling water
D. any onhe of the above methods

Answer

To prepare ferric hydroxide sol, follow these steps:

1. **Understanding Ferric Hydroxide**: Ferric hydroxide is represented by the chemical formula \( \text{Fe(OH)}_3 \). It is a colloidal solution that can be formed from ferric salts.

2. **Starting Material**: The preparation begins with ferric chloride (\( \text{FeCl}_3 \)), which is a soluble ferric salt.

3. **Dissolving Ferric Chloride**: Dissolve ferric chloride in water to create a ferric chloride solution. This can be done by adding a specific amount of \( \text{FeCl}_3 \) to distilled water and stirring until fully dissolved.

4. **Adding Base**: To precipitate ferric hydroxide, a base such as sodium hydroxide (\( \text{NaOH} \)) or ammonium hydroxide (\( \text{NH}_4\text{OH} \)) is added to the ferric chloride solution. The reaction that occurs is:
\[ \text{FeCl}_3 + 3\text{NaOH} \rightarrow \text{Fe(OH)}_3 \downarrow + 3\text{NaCl} \]
Here, \( \text{Fe(OH)}_3 \) is the ferric hydroxide that precipitates out of the solution.

5. **Formation of Sol**: The precipitated ferric hydroxide can be further treated to form a colloidal sol. This is typically done by adding the precipitate to boiling water and stirring. The heat and agitation help to disperse the ferric hydroxide particles, forming a stable colloidal solution.

6. **Final Product**: The resulting solution is a colloidal sol of ferric hydroxide, which can be used for various applications.