Did you know you can use chromatography to separate the different colours in the coating of colourful candy? This fun science experiment is perfect for learning about separating mixtures and can even be used as a science and art activity too!
This activity can also be found in my new book Snackable Science. If you click the image below you can download the instructions from the book in printable form! Hopefully it gives you a feel of what the book is like. There are 59 other edible activities to try, so plenty to keep everyone busy ( and well fed ) for a long time!
What is Chromatography?
Chromatography is a technique used to separate mixtures. The mixture is passed through another substance, in this case filter paper. The different colour ink particles travel at different speeds through the filter paper allowing us to see the constituent colours of the pen ink.
What you need for candy chromatography
M & Ms, Skittles or other coloured candy
Tray or plate
Place the candy onto a plate. It’s a good idea to use different colour sweets, so you can easily compare the results.
Carefully use a pipette to drop water onto the sweets and leave for a few minutes, until colour from the sweets dissolves into the water.
Use a pipette to suck up the coloured water and carefully drop onto the bottom of a strip of filter paper.
Use one strip for each colour of sweet.
Thread a paper clip through the filter papers and leave to rest in a test tube of water with just the bottom of the paper in the water,
Leave for about 10 minutes and observe what happens.
The filter paper shows different colour bands because the colouring on the candy shells is a mixture of colours. The colours that travel furthest up the filter paper are the most soluble!
Can you guess which filter paper was a green sweet?
Chromatography Extension Ideas
Try to separate felt tip pen colours. Investigate to discover whether you get the same results as with candy for each colour? For example, are the colours in a green Skittle and a green M&M the same?
If you enjoyed this investigation why not try our other exciting candy science ideas too.
How are mixtures separated?
Mixtures can be separated in lots of different ways, I’ve listed a few below.
- Mixtures with a solid suspended in a liquid can be separated by filtering. Try experimenting with a paper towel filter or sand and stone filter.
- Decanting is where a liquid is separated from a solid which has settled by pouring the liquid carefully out of the container leaving the solid behind.
- Centrifugation is where a substance is spun very quickly forcing the heavier particles to the bottom.
- Distillation is a process where mixtures are separated by heating. The vapour of the liquid with the lowest boiling point is released first. The vapours can then be condensed using something called a Liebig condenser.
More Chromatography Investigations
Add a bit of science to phonics learning with this fun chromatography and phonics activity.
Try some art and science with these chromatography butterflies
This activity is also found in Snackable Science!
Image credit below – Snackable Science
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Last Updated on May 24, 2021 by Emma Vanstone