Flashcards
Chromatography
Flashcards do conjunto (15)
- 1What is the mobile phase?Carries soluble components of the mixture with it (more soluble, faster movement)
- 2What is stationary phase?Holds back components attracted to it (more affinity, faster)
- 3What apparatus is used in TLC?Glass/metal/plastic sheet coated with thin layer of silica gel or alumina (stationary phase)
- 4What are the advantages of TLC?- runs faster
- small amounts can be separated
- spots spread out less
- plates more robust - 5What happens once the solvent has run?UV light or a locating agent is used to locate the colourless spots and make them visible
- 6what is rf?rf = distance moved by spot/distance moved by solvent
- 7What is the stationary phase in column chromatography?Uses a powder (silica/aluminium oxide/resin)
- 8How is the apparatus set up for column chromatography?- Powder packed into narrow tube + solvent added to top
- Eluent runs down column, components move at different rates, collected separately in flasks at bottom
- more than 1 eluent = better separation - 9What are the advantages of column chromatography?Large amounts can be separated and collected
- 10What is the stationary phase for gas liquid chromatography (GC)?Powder coated in oil
- 11What is the mobile phase for GC?unreactive gas
- 12What is the set up of the apparatus?- long capillary tube coiled in the oven
- sample moves along with gas and some retained by oils (components have different retention rates) - 13What is the advantage?Is very sensitive analysis
- 14What is GCMS?Gas chromatography mass spectrometry
- 15What is the process of GCMS?- GC column
- times noted
- into MS
- compound indentified
Informações
- Descrição
- AS level Chemistry (Chapter 33 - Chromatography) FlashCards sobre Chromatography, criado por Bethany Westwood em 10-01-2018.
- Criado por
- Bethany Westwood
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