We have looked at how objects absorb water before. Today we are taking this a step further and trying to halt the process, and so investigate which materials are good absorbers and which are not. We’re going to do this with a fun and very simple absorbing experiment.
What you need:
- Sugar cubes
- Food colouring
- Aluminium foil
- Cling film
- kitchen roll
Add a few drops of food colouring to some water and pour onto the plate.
Add a stack of sugar cubes and observe what happens. The coloured water should move up the stack of cubes and eventually make them collapse.
Try adding a small sheet of foil on top of one sugar cube and stack some more on top. Does this stop the water reaching the top cubes?
Try the same with some cling film, and some paper or tissue. Which work the best?
Which falls down first?
The Science Bit
The water is absorbed by the sugar cubes as you can see by the colour rising up through the cubes.Our foil and cling film did stop the flow of water for a while, but eventually it found a way through. I think we cut the foil/clingfilm a little small. These were the last stacks to fall though. The paper absorbed the water easily and let it reach the cubes above. This is because paper is porous and lets water pass through it. The foil and clingfilm prevent water passing through.
Simple science, absorbing experiment
Suitable for Key Stage 1 Science