Homemade Lava Lamp

We watched a video on a homemade lava lamp and we decided to make it. You need a bootle, testube etc. a verroca, pandol etc. some cooking oil and food colouring we all made a hypothises and tested it mine was that colours would mix and make one colour. My hypothises was correct the best mix we did was red and blue it made a royal purple and looked realy cool.