State three different materials that can be used to demonstrate Brownian motion.
Materials that can demonstrate Brownian motion:
Smoke particles suspended in air (in a smoke cell), viewed under a microscope.
Pollen grains suspended in water.
Fine dust or graphite particles suspended in water or air.
Note: a suspension of gamboge or sulphur particles in water is also acceptable. In each case the tiny visible particles are seen to move in continuous, random, zig-zag paths because they are bombarded unequally by the much smaller, fast-moving molecules of the surrounding fluid.
Smoke particles suspended in air (in a smoke cell), viewed under a microscope.
Pollen grains suspended in water.
Fine dust or graphite particles suspended in water or air.
Note: a suspension of gamboge or sulphur particles in water is also acceptable. In each case the tiny visible particles are seen to move in continuous, random, zig-zag paths because they are bombarded unequally by the much smaller, fast-moving molecules of the surrounding fluid.