Is Oil Lighter than Water?

We have been experimenting with water in lots of different ways in our Kowhanga. This experiment involved water, oil and food colouring. We wanted to find out what would happen if the two substances mixed together. 

We discovered that water is denser than oil, which is why oil sits on the top of water, because it is lighter! The food colouring was the most dense, and sank to the bottom. 

We also discovered that our results differed depending on how much oil we added to the water. Interesting stuff!