
Fig. 7.1 Food crust on ancient pottery
Fig.7.2 Paper chromatography separates molecules from a mixture. You may have done this with ink at school using filter paper.
The paper is called the "stationary phase". The water carrying the molecules is the "mobile phase".
Fig.7.3 In gas chromatography (GC) the stationary phase is a long fine silica tube with a special coating inside. This one is 60 metres long. The coating is the stationary phase and gas is the mobile phase.