HPLC chromatography lab (1.5 pts) what are the possible sources of errors that can lead to...
HPLC chromatography lab
- (1.5 pts) what are the possible sources of errors that can lead to lower percentage purity of the sample.
- (1 pts) What is the mobile phase used in your experiment?
- (1.5 pts) What happens to the retention time of Caffeine if you change the mobile phase to 100% Methanol (Retention time would increase or decrease)? Why?
- (1 pts) What happens to the retention time of Caffeine if you change the mobile phase to 100% water (Retention time would increase or decrease)? Why?
- (1 pts) What happens to the retention time of Caffeine if you change the runtime to 28 minutes (Retention time would increase or decrease)? Why?
- (1 pts) What happens to the signal shape if the concentration of the injected Caffeine sample is 2 M instead of 0.02 M.
Homework Answers
(i) a) contamination of the eluent with impurities, b) HPLC column may be contaminated with the previously analyzed compound.
(ii) Chloroform
(iii) Retention time would decrease because the caffeine is less soluble in methanol than in chloroform.
(iv) Retention time would decrease because the caffeine is less soluble in water than in chloroform.
(v) Retention time would increase as the run time is high.
(vi) The signal shape will be broad.
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HPLC chromatography lab
(1.5 pts) what are the possible sources of errors that can lead
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