Our first science session saw us investigating chromatography; the separation of a mixture. We thought about different colour mixes and tried to separate the colours from felt tip pens, to see if they were made up as we predicted. Firstly, we experimented on an absorbent piece of filter paper. We blotted felt tip pens, then used a pipette to drop water near the colour. We watched as the water was drawn up through the ink. This made the colour ‘run’, or travel. Some of the ink colour moved quicker than other parts, thus separating the different components. We saw different colours transpire. Once we knew how to extract the different colours we investigated different felt tips to see which gave the best results. Our favourites were black, grey and dark green. We used this technique to make wonderful pictures. You can easily try this at home using kitchen towel.
Science Club KS2 Week 1