Chromatography Flashcards
(1 cards)
How do you do paper chromatography?
1) Draw a line near the bottom of a sheet of filter paper. Use a pencil single the marks are insoluble.
2) Add a spot of ink to the line, and place the sheet in a beaker of solvent (e,g. water).
3) The solvent used depends on what’s being tested. Some compounds will dissolve well in water, but sometimes other solvents like ethanol are needed.
4) Make sure the ink isn’t touching the solvent so it doesn’t dissolve into it.
5) Place a lid on top of the container to prevent the solvent from evaporating
6) The solvent will start going up the paper, carrying the ink with it.
7) Each different dye in the ink will move up the paper at a different rate so the dyes will separate out. Each dye will form a spot in a different place. 1 spot per dye
8)if any of the dyes in the ink are insoluble in the solvent used, they will stay on the line.
9) When the solvent has nearly reached the top of the paper, take the paper out of the beaker and leave it to dry
10)the end result is a pattern of spots called a chromatogram
