Surface Tension

Surface Tension

Surface tension is a force

​which causes a layer of liquid to behave like an elastic sheet of skin.

What is surface tension?

• The high surface tension of water allows insects to walk over it.

• Pond skaters have long hairy legs,allowing them to spread their weight over a wide area.

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Multiple Choice

Water bugs can walk on water because of _______ tension.

• surface

• Santa Claus

• San Diego

Now, let's do our experiment!

Multiple Choice

The soap on my finger made the pepper ____________.

• change

• spread

Explanation Slide...

The soap is breaking the surface tension of the water! Surface tension exists in water because the water molecules (the little pieces of the water) like to stick together.

Water has high surface tension, which means the molecules like the pull towards each other and stick together very strongly. But, when soap is added to it, it breaks the surface tension. The molecules close to your fingers are pulled away by molecules that are farther away from your finger.