MChem Master of Chemistry Master of Chemistry: Analytical Chemistry 2

Question 1

Which chromatographic technique is most suitable for separating thermally labile biomolecules such as proteins?

Accepted Answer

High-performance liquid chromatography (HPLC)

Answer

HPLC operates at ambient temperatures in liquid mobile phases, making it ideal for thermally labile biomolecules like proteins.

Question 2

In inductively coupled plasma mass spectrometry (ICP-MS), what is the primary purpose of the collision/reaction cell?

Accepted Answer

To remove polyatomic interferences

Answer

The collision/reaction cell uses gases like helium or hydrogen to eliminate polyatomic spectral interferences that overlap with analyte masses.

Question 3

What does the term 'selectivity coefficient' (k_ij) represent in ion-selective electrode (ISE) potentiometry?

Accepted Answer

The ratio of the electrode's response to an interfering ion versus the primary ion

Answer

The selectivity coefficient k_ij quantifies how strongly an interfering ion j disturbs the electrode's response relative to the primary ion i.

Question 4

In Fourier-transform infrared spectroscopy (FTIR), what is the role of the beamsplitter?

Accepted Answer

To divide the IR beam into two paths for the interferometer

Answer

The beamsplitter in a Michelson interferometer divides the IR beam between the fixed and moving mirrors, creating constructive and destructive interference.

Question 5

Which statistical test is used to compare the precision (variance) of two analytical methods?

Accepted Answer

F-test

Answer

The F-test compares the ratio of two sample variances to determine if the precisions of two methods differ significantly.

MChem Master of Chemistry Practice Test

MChem Master of Chemistry Practice Test

MChem Master of Chemistry Master of Chemistry: Analytical Chemistry 2