Question

1.Summarize the benefits and weakness of flame, graphite furnace, and ICP as sources for atomic spectroscopy. Why is ICP used for this method?

2.Log-log plots are often used for ICP emission spectroscopy data. Why? Will a method that gives a linear beer’s law plot necessarily also give a linear log-log plot? Will using a log-log plot affect the calibration? Explain.

3.Briefly describe why an ICP-ES is able to observe elemental information in the visible light range, which is normally associated with electronic transitions of bonding orbitals.

4.What key spectroscopic tool is made possible by population inversion and stimulated emission? Explain.

Answer 1

Flame Atomic Absorption Spectrometry (FAAS)

Benefits: Easy to use, Very Fast, Lowest Capital Cost, Relatively few interferences, Very compact instrument, Good Performance, Robust interface

Weaknesses: Moderate detection limits, Element limitations, 1-10 elements per determination, No screening ability

Graphite Furnace Atomic Absorption Spectrometry (GFAAS)

Benefits: Very good detection limits, Small sample size, Moderate price, very compact instrument, few spectratl interferences

Weaknesses: Slower analysis time, chemical interferences, element limitations, 1-6 elements per determination, No screening ability, Limited dynamic range

Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES, or ICP)

Benefits: Easy to use, multi-element, high productivity, very economical for many samples or elements, few chemical interferences, robust interface, excellent screening abilities,high total dissolved solids, solid and organic samples

Weaknesses: Moderate to low detection limits (but often much better than FAAS), Spectral interferences possible, some element limitations.