When `FeC_3` solution is added to NaOH a negatively charged sol is obtained. It is due to the:

Options

A. Pressure of basic group
B. Preferential adsorption of OH ions
C. Self dissociation
D. Electron capture by sol particles

Explanation

To solve the question regarding the formation of a negatively charged sol when FeCl3 solution is added to NaOH, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in this scenario are FeCl3 (ferric chloride) and NaOH (sodium hydroxide).

2. **Reaction Between FeCl3 and NaOH**: When FeCl3 is mixed with NaOH, a chemical reaction occurs:
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