Chapter 7 Multiple Choice Questions

. Which of the following is one of the main advantages of coupling chromatography with mass spectrometry

Provides a tool to analyse complex samples containing many different analytes

Provides a tool for analysis of liquids and gases

Provides a tool for separating analytes in a complex mixture within the timeframe of a mass spectrometry experiment.

Enables absolute quantification without the need for external standards

. Which of the following is the correct way to indicate a liquid chromatography systems coupled directly to mass spectrometer according to 2013 IUPAC recommendations

LC/MS

LC-MS

LCMS

GCMS

. Which parameter from LC-MS or GC-MS analysis is proportional to analyte concentration?

Chromatographic retention time

Total ion chromatogram

Mass spectral m/z value

Chromatographic peak area

. Which of the following types of liquid chromatography is most suitable for the analysis of ionic compounds using mass spectrometry as a detector?

Normal phase chromatography

Reversed-phase chromatography

Ion Exchange chromatography

Nanoflow reversed phase chromatography

. Which type of chromatography typically utilises columns where the inner diameter is < 0.1mm

Capillary liquid chromatography

Nano-liquid chromatography

Ultra-high performance liquid chromatography

Ion-exchange chromatography

. Which of the following GC stationary phase is the least polar

Dimethylpolysiloxane

Diphenyldimethylpolypsiloxane

Cyanopropylphenyldimethylpolysiloxane

Polyethyleneglycol

. Which of the following statements best describes Ion Mobility Spectrometry couples to mass spectrometry (IMS-MS)

A gas-phase separation technique similar to gas-chromatography which separates molecules based on their mass to charge ratio.

A gas-phase or liquid—phase separation technique which separates molecules based on their mass to charge ratio.

A gas-phase or liquid—phase separation technique which separates molecules based on their mass to charge ratio and retention time.

A gas-phase ion separation technique that resolves molecules based on their charge and cross-sectional area, and detects them based on their mass to charge value.

. Which of the following is required when using a chromatographic system coupled to a mass spectrometer for absolute quantification of an analyte.

A very high resolution mass spectrometer

An authentic standard of the analyte

A high performance chromatography system

As many points on the calibration curve as possible

. If the equation for the line of best fit on an external calibration curve is y=1x10⁸χ + 18474. What is the concentration of the analyte from which it is derived (in µg/mL to 1 d.p.) if the peak area for the analyte from a sample of unknown composition is 25000000.

4.9 µg/mL

5.0 µg/mL

2.5 µg/mL

1.5918 µg/mL

. Which of the following best explains why higher sensitivity leads to lower error in the quantification of an analyte.

Higher sensitivity leads to higher spectral accuracy and hence lower limit of detection.

Higher sensitivity leads to lower quantification error because resolution is increased.

Higher sensitivity leads to lower precision but higher limit of detection.

Higher sensitivity leads to higher precision in the determination of concentration and a lower limit of detection.

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