Factors contributing to the higher stability of lyophilic colloids:

The stability of a lyophilic colloid refers to its ability to stay dispersed in a solvent or dispersion medium without undergoing flocculation or coagulation. Several factors contribute to the stability of lyophilic colloids, including:

1. Charge on their particles:
The presence of charges on the particles of a colloid can lead to electrostatic repulsion between them, preventing their aggregation. However, in the case of lyophilic colloids, the particles are usually electrically neutral or have a very low charge. Therefore, the charge on their particles does not play a significant role in their stability.

2. Attractive forces between particles:
In lyophilic colloids, the attractive forces between particles are relatively weak. These weak forces, such as van der Waals forces, London dispersion forces, and dipole-dipole interactions, are not strong enough to cause significant aggregation or precipitation. Hence, the attractive forces between particles do not contribute much to the stability of lyophilic colloids.

3. Small size of their particles:
Smaller particles have a larger surface area, which increases the repulsive forces between them. This makes it more difficult for the particles to come close enough to form aggregates. Therefore, the small size of the particles in lyophilic colloids enhances their stability.

4. High solvation due to a layer of dispersion medium:
The most crucial factor contributing to the higher stability of lyophilic colloids is the presence of a layer of dispersion medium adsorbed onto the surface of the particles. This layer is formed due to the strong interaction between the particles and the dispersion medium. The solvent molecules form a solvation layer around the particles, providing a protective barrier that prevents particle-particle interactions. This solvation layer acts as a stabilizing force, keeping the particles dispersed and preventing their aggregation. The high solvation of lyophilic colloids due to the presence of a layer of dispersion medium is the correct answer (option D) for the question.

In conclusion, the stability of lyophilic colloids is primarily attributed to the high solvation of particles due to a layer of dispersion medium adsorbed onto their surface. This solvation layer acts as a protective barrier and prevents particle-particle interactions, thereby maintaining the colloidal dispersion.