ANS:D - difference between adhesive & cohesive

Adhesive and cohesive forces are both types of intermolecular forces, but they act between different types of molecules and have different effects:

1. Cohesive Forces:
   • Cohesive forces are the intermolecular forces that bind similar molecules to one another. For example, in a liquid, cohesive forces act between molecules of the same substance.
   • These forces tend to pull molecules of the same substance together, creating a strong attraction between them.
   • Cohesive forces are responsible for phenomena such as surface tension, where molecules at the surface of a liquid are pulled inward due to cohesive forces, creating a "skin" on the surface.
2. Adhesive Forces:
   • Adhesive forces are the intermolecular forces that act between different types of molecules. For example, in a liquid-solid interface, adhesive forces act between molecules of the liquid and molecules of the solid surface.
   • These forces tend to attract molecules of different substances to one another.
   • Adhesive forces are responsible for phenomena such as adhesion, where a liquid spreads out and adheres to the surface of a solid.

In summary, cohesive forces act between molecules of the same substance, while adhesive forces act between molecules of different substances. Both types of forces play important roles in various natural phenomena and processes, including surface tension, adhesion, and capillary action.