chromatography - required practical

Cards (8)

what is the aim of the practical
find out the composition of the unknown mixture by comparing it to known substances
what is the setup of the practical
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why should the origin line be be drawn 2cm from the bottom edge of the paper
to give room for the solvent to travel without submerging the substance causing it to diffuse all over the paper
why cant the sides of the paper touch the beaker
it can disrupt the even flow of the solvent up the paper leading to uneven separation of the components
why should you allow the chromatography paper to dry before calculating Rf values
to prevent the spots from continuing to move or diffuse allowing accurate distance measurements for calculations
what should the results look like  
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what do we do with these results
calculate the Rf value and see which of these match with our unknown substance
what is the conclusions of the results
out of the 3 substances in solvent x we know 2 ( A + D ) by utilizing the known substances