The stability of lyophobic sols is due to the charge on particles.

Explanation:
Lyophobic sols are colloidal sols in which the dispersed phase (colloidal particles) has little or no affinity for the dispersion medium. This means that the particles are not easily dispersed in the medium and tend to aggregate or settle quickly. However, the stability of lyophobic sols is achieved by introducing charges on the particles.

The charge on particles in lyophobic sols is usually achieved through the process of adsorption. When a lyophobic sol is prepared, the dispersion medium is treated with a suitable electrolyte. This electrolyte dissociates into positive and negative ions, and these ions get adsorbed on the surface of the particles. The adsorption of these ions imparts a charge to the particles, creating a stable colloidal system.

The charge on particles plays a crucial role in stabilizing lyophobic sols. Here's why:

1. Electrostatic Repulsion: The like-charged particles repel each other due to electrostatic forces. This repulsion prevents the particles from coming close together and aggregating. As a result, the sol remains stable and the particles stay dispersed.

2. Steric Stabilization: In addition to electrostatic repulsion, charged particles may also have adsorbed layers of molecules or ions that create a physical barrier around the particle. This is known as steric stabilization. The adsorbed layers prevent the particles from approaching each other closely, further enhancing the stability of the sol.

3. Prevention of Coagulation: The charge on particles hinders the process of coagulation or flocculation. Coagulation occurs when colloidal particles come together to form larger aggregates. The charged particles repel each other, making it difficult for coagulation to occur.

4. Redispersion: If the sol undergoes slight flocculation or settles, it can be easily redispersed by gentle shaking or stirring. The charged particles will disperse again due to repulsion forces.

In summary, the stability of lyophobic sols is primarily due to the charge on particles. This charge creates repulsion forces that prevent aggregation and coagulation of particles, thus maintaining the sol's stability.