Fb-5 Reducing Surface Tension
Aim
To demonstrate the reduction of surface tension.
Apparatus
- Large beaker
- Stocking
- Water, soap solution
- Overhead projector
- Wire gauze mat as shown
- Medicine dropper
Description
A stocking floats in a beaker of clean water. The addition of a few drops of soap solution reduces the surface tension sufficiently and the stocking sinks.
A large droplet of water is placed on the wire gauze mat. The surface tension of the water gives it its roughly spherical shape. The addition of a small drop of soap solution reduces its surface tension and "spreads" the drop.