Primary School

Relationships. Wellbeing. Achievement.

Week beginning 6.7.20

Surface Tension 


Surface Tension is an effect where the surface of a liquid is strong. The surface can hold up a weight, and the surface of a water droplet holds the droplet together, in a ball shape. Some small things can float on a surface because of surface tension, even though they normally could not float. Surface tension is the result of the surface-level molecules of water being pulled downward by attraction to other molecules.


When you add pepper to water, the pepper should float. We want to see if you can make the pepper either sink or move to the side by breaking the surface tension. To do this you will need: 


A bowl of water

Dish soap. 


You will need to put your pepper in the water. You should now see that the pepper is floating. Once you have done this dip your finger in dish soap and then place it in the water. What happens?