Question

The surface tension of a liquid at its boiling point

• A. becomes zero
• B. becomes infinity
• C. is equal to the value at room temperature
• D. is half of the value at room temperature

Hint:

Surface tension becomes zero at the critical temperature (boiling point) where liquid and gas phases become indistinguishable.

Answer 1

The Correct Option is A

At the boiling point, the liquid converts to vapor and intermolecular forces reduce significantly. As surface tension is due to cohesive forces, it vanishes at boiling point. \[ \text{Therefore, } \text{Surface Tension} = 0 \]