CHROMATOGRAPHIC
PLATE (noun)
A small
sheet of glass or aluminum, coated on one side with the substance that makes
up the stationary
phase in a chromatography
experiment. The substance used can be, for example, silica gel or Al2O3,
and is usually white in color and feels like chalk. In paper chromatography,
the paper can serve as both the material of which the plate is constructed
and the stationary
phase.