a) Define surface tension.
(b) State two methods by which the surface tension of a liquid can be reduced.
Explanation
(a) Surface tension is the force per unit length acting in the surface at right angles to one side of a line drawn in the surface of a liquid. It can be defined as the property of a liquid that makes it behave as if its surface is an elastic skin.
(b) Methods of reducing surface tension are by adding:
– Soap
– alcohol
– oil
– detergent
– increasing the temperature.