In case of surface of one fluid in contact with other fluid or solid surafce , surface tension/surface energy depends on what ? Explain with illustration.

Explanation

In the case of surface of one fluid in contact with other fluid or surface ,the surface tension depends on the materials on both sides of the surface.
For example :
(i) If the molecules of the material attract each other , surface energy is reduced.
(ii) If they repel each other the surface energy is increased.
Thus , more appropriately , the surface energy is the energy of the interface between two materials and depends on both of them .