Did you know that you can grow your own rainbow?
We are going to have a go this week!
This science experiment involves a process called the capillary action. This action happens when a liquid moves up through a hollow tube or into a spongy, solid material. It happens when three forces work together: cohesion, adhesion and surface tension.
Water molecules like to stick to each other - this is called cohesion. They also like to stick to solids in a process called adhesion.
In this experiment, you are going to use kitchen roll. The fibres in kitchen roll have lots of little holes. Water is absorbed through the kitchen roll because when the first water molecule adheres to it and begins to move upward, it pulls the next water molecule up with it, like a chain.
Watch the video and then have a go at completing the experiment yourself if you are able to! Then, complete the evaluation below.
You will need:
- Kitchen roll
- Felt tip pens
- Two small bowls or cups of water
PDF document available above for your evaluation.
Alternatively, record your answers on paper or submit a note/recording to seesaw.
Make sure to take some photos or videos and upload these to seesaw - I'd love to see how you got on!