1. Describe Partitioning in Liquid-Liquid Extraction. Include any relevant equations, such as that for the partition coefficient.
2. Which is better, one large extraction, or a series of smaller ones that add up to the same extracted volume?
3. How does pH affect the partition coefficient? Examine organic species and complexes of metal ions.
4. What is Chromatography? Define and explain solid support, stationary phase, mobile phase, and partition coefficient (equation).
5. How does gas-liquid chromatography (GLC) work? Sketch a diagram of a typical instrument.
6. In GLC, which gives better resolution, a packed column or a capillary column? Why? In answering this, use the chromatographic terms such as particle size, flow rate, temperature, longitudinal diffusion, partition coefficient, equilibration rates. The discussion of the factors behind the Van Deempter equation may prove helpful here.
7. What factors influence the choice of the stationary phase in a GLC column? Begin your discussion with polar vs. non-polar columns.
8. What is temperature programming in GLC and what advantages does it offer? What is meant by running "isothermally?"
9. What must we consider when choosing a temperature for the injector, detector, and column in GLC?
10. Important GLC detectors include Thermal Conductivity (TCD), Flame Ionization (FID), Electron Capture (ECD), and Mass-Spectrometry (GC-MS). Describe how each of these works and state its main advantages.
11. How does High Performance Liquid Chromatography (HPLC) work? Sketch a diagram of a typical instrument. Include HPLC things such as guard columns and sample loops.
12. What are the advantages of HPLC over GLC?
13. How does choice of solvent type and factors such as pH affect the partitioning process in HPLC? In responding, assume we are using a typical non-polar C-18 column in so-called "reverse phase" chromatography.
14. What is solvent programming in HPLC? What advantages does it offer? What is meant by running "isocratically?"
15. Spectrophotometric detectors are probably the most common in HPLC. Describe how these work.
16. Describe a typical anion exchange resin and cation exchange resin. Then diagram an ion chromatograph and explain how it works.
17. Explain how Internal Standards are used in quantitative HPLC and GLC to make working curves and determine unknowns.