Chemical Analysis Flashcards
1
Q
Artificial colours can be separated using [ ]
A
paper chromatography
2
Q
State the process of chromatography to find out how many/which dyes are in food colouring (5)
A
1) extract the colour from a food sample by placing it in a small cup with a few drops of solvent
2) Put spots of the coloured solution on a pencil baseline on filter paper.
3) Roll up the sheet and put it in a beaker with some solvent - but keep the baseline above the level of the solvent
4) The solvent seeps into the paper taking the dyes with it. Different dyes form spots in different places
5) However a chromatogram with 4 spots means at least 4 dyes not just for dyes.
3
Q
What can you use as a solvent to extract colour from food samples?
A
Water, ethanol and salt water
