CHEM 212 Lecture 33: Nov 22, 2016

• School: University of Victoria
• Department: Chemistry
• Course: CHEM 212
• Professor: Hamilton M.Coreen

Document Summary

H proportional a+ b/mu + cmu mu= ow rate two terms are ow rate dependent. Every molecule has a di erent path length to get from one end of the column to the other side of the column. If all particles took the same amount of time. Pushing them through faster does not a ect therefore not ow rate dependent. Gc does not have an a term bc there is no little p articles, its walls that are coated, therefore eddy term is very minor is gc. Van deemter eqn works for both gc and liquid chromatography. You add broadness to the peaks if you are slow at injecting the sample, our labs have autosamplers. Faster ow rate the less time sample spends on column, therefore less di usion. -> faster ow rates means less broadening due to eddy di usion. Only important in gc (^ dmp of a gas)