Surface tension of a liquid is a molecular phenomenon of liquids involving the force of cohesion among the liquid molecules. It is a scalar quantity and numerically equal to the surface energy. Numerically, it is proved that the potential enenergy of a liquid is maximum on the surface. Sparingly soluble salts and surface active substances decrease the surface tension of the liquid, however, the fairly soluble solute increase is independent of surface area but if depends on the intermolecular force and the temperature.
Surface tension of a liquid is zero at:
A. inversion temperature
B. boiling point
C. critical point
D. saturation point