In paper chromatography, why do different substances move different distances?
Answer and explanation
Correct answer: D. They have different attractions for the paper and the solvent
- Step 1: Substances more attracted to the solvent move further.
- Step 2: Those held by the paper move less, so the mixture separates.
Answer
They have different attractions for the paper and the solvent.
Why not the others: They have different colours: colour does not control movement. They have been heated to different temperatures: the temperature is not the reason. They are made of the same chemicals: then they would move together.
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