Modern Analytical Techniques II Flashcards
what happens if sample components are not coloured
locate the spots on the chromatogram
Using: UV light, Ninhydrin , Iodine vapour
What is mobile phase
allows molecules to move over or through the stationary phase. Can be in liquid or gas form
What is stationary phase
The stationary phase is a substance that has affinity to molecules in the mixture being analysed.
The greater the affinity of a molecule to the stationary phase, the shorter the distance and/or the slower it moves within the mobile phase.
What is TLC
a metal plate is coated with a thin layer of silica and the sample being analysed is dotted on the plate.
What is column chromatography
vertical column packed with a solid powdered substance which acts as a stationary phase
what is retention time
Time taken for substance to travel down the column
why is HPLC an improved form of column chromatography
uses high pressures to force mobile phase through column.
Gas chromatography
thin tube packed with a solid powdered substance which acts as a stationary phase. High pressure gas passed through which acts as a mobile phase. Separates mixtures of volatile liquids
what does analysis machine record
retention time for each component molecule in the mixture allowing them to be indentified
