Chromatography Flashcards
What is chromatography?
A method used by chemists to separate out mixtures.
What is paper chromatography primarily used for?
To separate out dyes in inks, paints, food colourings, etc.
What is the first step in performing paper chromatography?
Draw a line near the bottom of a sheet of filter paper.
Why should the baseline be drawn with a pencil?
Pencil marks are insoluble and won’t dissolve in the solvent.
What should be done after adding spots of different inks to the baseline?
Loosely roll the sheet up and put it in a beaker of solvent.
What is an example of a solvent that can be used in paper chromatography?
Water or ethanol.
Where should the level of solvent be in relation to the baseline?
Below the baseline.
Why is it important to keep the solvent level below the baseline?
To prevent the inks from dissolving directly into the solvent.
What is the purpose of placing a lid on top of the container during chromatography?
To stop the solvent from evaporating.
What happens when the solvent seeps up the paper?
It carries the inks with it.
What occurs when different dyes are carried up the paper?
Each dye moves at a different rate and forms a spot in a different place.
What is the final result of a paper chromatography experiment called?
A chromatogram.
What can happen if you use a pen to draw the baseline instead of a pencil?
The components of the ink in the pen will get separated, making results confusing.
