Chromatography MCQ

Question 1

What is the primary purpose of chromatography?
a) To heat and vaporize samples
b) To separate components of a mixture
c) To detect microbial contamination
d) To measure blood pressure

Answer 1

b) To separate components of a mixture

Question 2

Which phase in chromatography remains stationary?
a) The liquid phase
b) The mobile phase
c) The column phase
d) The stationary phase

Answer 2

d) The stationary phase

Question 3

What property primarily determines separation in gas chromatography?
a) The boiling points of the sample components
b) The sample’s electrical conductivity
c) The molecular weight of the compounds
d) The pH of the mobile phase

Answer 3

a) The boiling points of the sample components

Question 4

What is the most commonly used stationary phase in Thin Layer Chromatography
(TLC)?
a) Liquid nitrogen
b) Silica gel or alumina
c) Carbon fiber
d) Sodium chloride

Answer 4

b) Silica gel or alumina

Question 5

High-Performance Liquid Chromatography (HPLC) operates under:
a) Low pressure
b) High pressure
c) No pressure
d) Variable voltage

Answer 5

b) High pressure

Question 6

In chromatography, what is retention time?
a) The time taken for the sample to evaporate
b) The duration for which the mobile phase is stored
c) The time it takes for a compound to pass through the column
d) The time taken for the instrument to reset

Answer 6

c) The time it takes for a compound to pass through the column

Question 7

Which detector is commonly used in HPLC for identifying UV-absorbing compounds?
a) Mass spectrometer
b) UV-visible detector
c) Thermal conductivity detector
d) Infrared detector

Answer 7

b) UV-visible detector

Question 8

What is a common cause of peak broadening in chromatography?
a) Using a too-small sample volume
b) Using a short column
c) Slow diffusion of analytes in the stationary phase
d) Running the column at too high a temperature

Answer 8

c) Slow diffusion of analytes in the stationary phase

Question 9

Which chromatography technique is best for analyzing volatile compounds?
a) Gas chromatography (GC)
b) Thin layer chromatography (TLC)
c) Ion exchange chromatography
d) Gel filtration chromatography

Answer 9

a) Gas chromatography (GC)

Question 10

What is a common troubleshooting step when chromatographic peaks are poorly
resolved?
a) Increase the sample size
b) Use a longer column with a different stationary phase
c) Increase the speed of the mobile phase
d) Run the test without a stationary phase

Answer 10

b) Use a longer column with a different stationary phase