We always see these cool lava lamps in the shops and decided to use science to make our own. This is an awesome activity to enjoy by the older kids as well as the young ones.
You will need:
– a bottle
– food coloring
First, we filled the bottle three quarters with water.
We added a few drops of food coloring together with the glitter.
Then, we filled the bottle to the top with oil and gave it a stir. We were surprised to see that we created a tornado in the water when we stirred. The secret is that oil is less dense than water and therefor will keep on going to the surface even when stirred.
We started to add a spoon of salt and saw how the salt made bubbles looking like those in a lava lamp. (When the bubbles stop just add more salt.)
The salt is more dense than water and will go to the bottom. When we poured salt into the oil and water mixture, the oil stuck to the salt and sank to the bottom. The salt dissolved and the oil moved back to the surface. This effect creates the exciting show in the water.
Use a torch to see how the salt creates the drops in the water. Depending on the angle of the torch, it creates a beautiful light display.
A super cool DIY lava lamp using science!