Explain the phenomenon of surface tension on the basis molecular theory.

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Surface Tension**: Surface tension is a physical property of liquids that causes them to behave as if their surface is covered with a stretched elastic membrane. This phenomenon arises due to the cohesive forces between liquid molecules.

2. **Molecular Arrangement**: In a liquid, molecules are closely packed and interact with each other through attractive forces. These forces are known as cohesive forces.

3. **Molecules at the Surface**: Consider a liquid in a container. Molecules inside the liquid (like molecule A) are surrounded by other molecules on all sides. The cohesive forces acting on them are balanced, resulting in no net force acting on them.

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