HOW DO YOU CREATE A PAPER CHROMATOGRAPH?
A. Materials needed:
- A glass of water.
- Filter paper or toilet paper.
- Different colours of water-soluble markers.
- A ruler.
- Cut a rectangular strip of paper out of the toilet paper.
- Use the pencil to draw a horizontal line, about 2cm from the bottom of the strip of paper.
- Draw dots onto the line using the different coloured markers.
- Gently place the strip of paper into a glass of water, making sure the water level is below the pencil mark.
- Wait for about 15 minutes.
- You should see that the colours have travelled up the paper.
SO HOW DOES THE CHROMATOGRAPH WORK?
Chromatography is a method of separating mixtures. The process requires two phases of materials: The mobile phase which is usually a liquid or a gas and the stationary phase which is usually solid, in this case, the paper. As the liquid rises up the fibres of the paper through capillary action, some of the compounds within the inks will be attracted to the mobile solvent, thereby dispersing the inks into their component colours.
TAKING IT FURTHER
Try using different solvents such as salt solution, vinegar and alcohol as the moving agents. How do these affect your results? Why?