Chromatography Flashcards
Polar compounds move…
Non-polar compounds move…
slowly, eluted less readily
More quickly
The more polar the solvent,
the more quickly the components will move.
For a weakly adsorbed component you should use a _________ solvent.
Non polar
Polar compounds are
alcohols, carboxylic acid (RCOOH), and amides (RCONH@) All others are non polar
How can you visualize a spot plate?
UV light or an iodine chamber
In using TLC, you must always spot…
A standard compound for a reference
Solvents should be…TLC and column….
As non polar as possible to still allow movement
How would you find the best solvent to use in column chromatography?
TLC
Column chromatography advantages?
simple apparatus, and very high purity
Column chromatography disadvantages?
time consuming, must empirically determine adsorbent and solvent, not convenient for large quantities
What would happen if you used to much solvent to dissolve your compound?
Might run before it actually does, eluted faster
What does sand do?
Levels the alumina layer and evenly distributes the solvent before hitting the alumina
