Analytical Techniques

Question 1

How is resolution described?

Answer 1

It describes how well two bands are separated. Experimentally resolution is a measured as the retention time difference between two peaks divided by the average extrapolated with of the peak bases.

Question 2

How is column efficiency described?

Answer 2

It is described by the height of a theoretical plate(H) (smaller height for more efficient columns), the number of theoretical plates (N) and column height (L)

Question 3

How can you excited a molecule from its ground state to a higher E state?

Answer 3

The exact amount of energy equal to the the difference between the two states has to be absorbed.

Question 4

Molecular absorption spectra measures?

Answer 4

It measures the amount of e.m.r at a specific energy or wavelength absorbed by a molecule.

Question 5

What are ways an excited electron an lose its excess energy?

Answer 5

• Releasing E as heat
• Transferring its remaining E to others chemical species.
• Emitting photons when falling back to the ground state- fluorescence
• Undergoing internal transition within the same mode of the excited state.
• Undergoing intersystem crossing to a triplet sub level of the excited state.
• Radiating E from triplet to ground state (triplet quenching)