Colourful Chromatography

Year 5 continued with their scientific quest to hone their chemistry practical skills – this time with the colour chemical separation technique of chromatography.

A pencil line is carefully drawn onto filter paper and a dot of felt tip pen (the solute) is placed upon the line. The water (solvent) dissolves the felt tip pen and makes a solution. As the water carries the colours up the paper, the heavier pigments are left behind and the lighter ones travel higher.

The Year 5 classes were surprised to learn this is exactly the same practical which is performed at GCSE level – the only difference being the older children have to work out a calculation where you divide the total distance travelled by the highest line and the original dot. Some of the Year 5s were very much up for a spot of dividing, and went ahead and did that bit too!

We got some beautiful results and some showed there were 5 or 6 colours including red, green, yellow, purple, blue and brown hidden in the black pens!

Well done Year 5 – your practical was nothing short of spectacular!