Paper chromatography Flashcards
what is paper chromatography used for?
to separate substances based off their solubility
what is the stationary phase
this is what doesn’t move eg the paper
what is the mobile phase
what moves up the stationary phase eg the solvent
how will a pure substance look in paper chromatography
produces a single spot in all solvents
how will a compound look in paper chromatography
separates into different spots
why do we draw the starting line with a pencil
its insoluble and will not move up the paper
if a substance is more soluble does it travel higher up the paper or lower?
higher
how do we measure rf value?
distance moved by substance/ distance moved by solvent
how would we carry out paper chromatography?
- draw the starting line with pencil
- put a small dot of the compound on the line
- fill a beaker with shallow solvent, paper shouldn’t be touching the sides and starting line shouldn’t touch solvent
- add lid to avoid evaporation
- let the solvent travel up 3/4 of the paper then remove it and calculate rf values