Question

On what factor does the magnitude of the surface tension of a liquid depend?

Answer 1

Surface tension:

1. It may be defined as the property of the surface of a liquid that allows it to resist an external force, due to the cohesive nature of its molecules.
2. In other words, Surface tension is the tendency of fluid surfaces to shrink into the minimum surface area possible.
3. We can observe this phenomenon in the nearly spherical shape of small drops of liquids and of soap bubbles.
4. Because of this special property, some insects can stand on the surface of the water.
5. Mathematically, surface tension can be expressed as follows:
6. $T=\raisebox{1ex}{$F$}\!\left/ \!\raisebox{-1ex}{$L$}\right.$, Where $T$=Surface tension of the liquid, $F$= force per unit length, $L$= length in which force act,
7. Thus, Surface tension is directly proportional to the intermolecular forces of the liquid.
8. Surface tension is caused by the effects of intermolecular forces at the interface of the molecules.
9. Surface tension mainly depends on the nature of the liquid, the surrounding environment and temperature.
10. Liquids, where molecules have large attractive intermolecular forces, will have large surface tension.

Thus, Surface tension of a liquid depends upon the Temperature, Intermolecular forces, Pressure and Viscosity of that liquid.