Chemical analysis Flashcards
1
Q
What is chromatography
A
is a technique which can be used to separate identify and in some instances obtain individual substances from complex mixtures.
2
Q
What are the chromatographic methods
A
paper, thin layer, gas and liquid-gas
3
Q
How does chromatography work
A
The principles are the same
the differences in size and polarity of molecules are used to separate them. A liquid or gas (mobile phase) carries the molecules of a substance over or through a solid or a liquid absorbed onto a solid (stationary phase)
4
Q
The speed at which the compounds move depends on 2 factors:
A
- how attracted they are to the stationary phase
- their solubility in the mobile phase(solvent)
5
Q
what is a standard solution
A
A solution of accurately known concentration
6
Q
A
