SME
Analytical Chemistry · Problem type
Which chromatography for the sample?
Use this for “Which technique would you use to measure the chloride and bromide ions in a well-water sample?”
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Which technique separates this sample best?
Tap a card, then tap its group.
Ask first whether the compounds are volatile and stable when hot, then whether they are ions, and then whether size is what sets them apart.
Assumptions
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Gas chromatography needs compounds that boil without breaking down, carried by a gas.
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Reversed-phase HPLC suits neutral molecules that dissolve in water or methanol and would not survive heating.
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Ions go to ion-exchange; big molecules sorted by size go to size-exclusion.
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Related lessons
Chromatography
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Use this for “Two compounds have α = 1.08 and k₂ = 3.2 on a column. How many plates give a resolution of 1.5?”