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Question 18M.3.SL.TZ2.c.i

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Date May 2018 Marks available [Maximum mark: 1] Reference code 18M.3.SL.TZ2.c.i
Level SL Paper 3 Time zone TZ2
Command term Suggest Question number c.i Adapted from N/A
c.i.
[Maximum mark: 1]
18M.3.SL.TZ2.c.i

Chromatography is a technique used to separate the components of a mixture. The photosynthetic pigments from three organisms were separated by thin layer chromatography: spinach (Spinacia oleracea), a red alga (Porphyra) and a brown alga (Fucus).

Porphyra also contains phycoerythrin, which is a red pigment.

Suggest a reason for phycoerythrin being absent from the Porphyra chromatogram.

[1]

Markscheme

a. the pigment didn't dissolve / was insoluble when the pigments from the algae were extracted 

b. the pigment was not moved by / was insoluble in the solvent used to separate the pigments

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