High-Performance Liquid Chromatography Deck (Exam 2)

Question 1

What are the 2 types of mobile phases in HPLC?

Answer 1

Normal and reverse

Question 2

In HPLC, what type of mobile phase complements a polar stationary phase?

Answer 2

Normal

Question 3

In HPLC, what type of mobile phase complements a non-polar stationary phase?

Answer 3

Reverse

Question 4

What is the difference between isocratic and gradient elution?

Answer 4

Isocratic elution uses a single/constant solvent while gradient involves adding increasing amounts of a second solvent to the first for a continuous gradient

Question 5

What are the 2 configurations for HPLC’s 6-port loop injector?

Answer 5

Load and inject

Question 6

What is the purpose of setting a gradient elution?

Answer 6

To maximize retention time while also moving components through column faster

Question 7

Why should you use a buffer for reverse phase HPLC?

Answer 7

To keep target analyte in non-salt form to maximize interaction with the column

Question 8

How concentrated should the buffer used for reverse phase HPLC be?

Answer 8

As low as possible but still about to provide reproduceable results

Question 9

What is the purpose of internal standards in HPLC?

Answer 9

For quantitative use and calibration

Question 10

Target analytes for HPLC should be the opposite condition as they are in GC. Meaning they should be { } and { }.

Answer 10

Non-volatile & thermally labile

Question 11

Is derivatization necessary for HPLC?

Answer 11

No