Read the given passage and answer the question that follow:
Colloidal particles always carry an electric charge which may be either positive or negative. For example, when `AgNO_3` solution is added to KI solution, a negatively charged colloidal sol is obtained. The presence of equal and similar charges on colloidal particles provide stability to the colloidal sol and if, somehow, charge is removed. coagulation of sol occurs. Lyophobic sols are readily coagulated as compared to lyophilic sols.
What is the reason for the charge on sol particles ?

Explanation

To answer the question regarding the reason for the charge on sol particles, we can break down the explanation step by step:

### Step-by-Step Solution:

1. **Understanding Colloidal Particles**:
Colloidal particles are tiny particles that can remain suspended in a medium. They can carry either a positive or negative electric charge.

**Hint**: Remember that colloidal particles are small and can exist in different charge states.
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