What is chromatography?
Chromatography is a technique that is used to separate mixtures into their original parts, allowing you to identify the chemical components.
In this experiment from Buggy & Buddy, you can use chromatography to separate the colours in markers. What colours make brown? Are different brown markers made up of the same colours?
How does Chromatography work?
As the liquid travels up the paper, it carries the ink along with it. Different coloured inks travel at different rates along the paper. In this way, the individual colours separate, so you can identify them.
Introduction to Paper Chromatography from ChemGuide
Paper Chromatography for Middle and High School Students from Amy Brown Science
How Does Chromatography Work from Explain That Stuff