4 October 2018
This week in the Eureka Science Club for Y5 and Y6, we made erupting fizz to create a 'lava lamp' type effect – the experiment demonstrates that oil and water don't mix.
In a beaker of fizzy water with a layer of oil on top, when you put in a load of salt all at once, it sinks some of the oil, which then rises back up due to the fizz. You can keep it fizzing and prolong the effect by adding bits of effervescent tablet. Adding food colouring lets you see the globules better.