Question

When a soluble substance such as common salt (i.e., sodium chloride) is dissolved in water, the surface tension of water ______.

Options

• decreases

• becomes zero

• remains the same

• increases

Answer 1

When a soluble substance such as common salt (i.e., sodium chloride) is dissolved in water, the surface tension of water increases.

Explanation:

1. When common salt (NaCl) dissolves in water, it breaks into Na⁺ and Cl⁻ ions.
2. These ions attract water molecules, increasing the cohesive forces at the surface.
3. As a result, the surface tension of water increases.