Question

surface tension chemistry

Answer 1

Surface tension is a physical property equal to the amount of force per unit area necessary to expand the surface of a liquid. Surface tension forces is due to intermolecular forces between the liquid's molecules 

Answer 2

The liquid molecules which are below the surface are in equilibrium.  The liquid molecules which are at the surface are attracted by other molecules in downward direction. So, a force is originated to balance the surface molecules which is equal but opposite in direction to the downward force. This force is called surface tension.