COMEDK2021PhysicsMechanical Properties of Fluids
The surface tension of a liquid at its boiling point
Options
- Abecomes zero
- Bbecomes infinity
- Cis equal to the value at room temperature
- Dis half of the value at room temperature
Correct answer
A. becomes zero
Step-by-step solution
Surface tension is a property of liquids that arises due to the cohesive forces between molecules at the surface. As the temperature of a liquid increases, the kinetic energy of the molecules increases, which weakens the intermolecular forces of attraction. At the boiling point, the liquid is in equilibrium with its vapor phase. The density of the liquid phase decreases while the density of the vapor phase increases as the temperature approaches the critical temperature. At the critical temperature, the distinction