National Chemistry Week - Experiments - Rainbow in Your Room

THE AIM:

To observe the separation of colours in white light using water.

WHAT YOU WILL NEED:

• flat mirror
• pan of water or water table
• strong light source (flashlight)
• dark room

WHAT TO DO:

1. Place the mirror under the water so that the end is submerged.
2. Use the flashlight to reflect light off the submerged mirror.
3. Look for the rainbow in the room. It could be on a wall or the ceiling.

The light that comes from the flashlight is made up of all the colours of the rainbow (red, orange, yellow, green, blue, violet). Water bends light that enters into it. Some colours of light are bent more than others. The result is a rainbow in your room.

When there is sunshine and rain at the same time, the water drops from the rain break the sunlight into its colours, and this is what causes a rainbow outside. You can make a rainbow outside on a sunny day by placing the sun at your back, and spraying a hose in front of you; a rainbow will be visible in the mist from the hose.