f e rp 7fe xlfJJ1 1 IWJb rnic I J Why do you only need to monitor UV absorbance

F e rp 7fe xlfjj1 1 iwjb rnic i j why do you only

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\ f e ; r{p�� ') =7fe_ xlfJJ1� 1 -- IWJ:b rnic /I<: J Why do you only need to monitor UV absorbance at a single wavelength? Sandy Student remembers that you can also derive relative abundances via NMR and suggests that you just place your crude mixture from Q7 in an NMR instrument instead. Why is this a bad idea? 4
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,, / Just as hard-to-vaporize compounds can cause trouble for gas chromatography, they are also problematic for mass spectrometry, which can only analyze gas-phase compounds. Matrix Assisted Laser Desorption Ionization (MALDI) helps these compounds vaporize by mixing them with another compound (the "matrix") that can absorb laser light. When the laser is turned on, some of the absorbed energy is transferred to the target compound, which "sputters" into the gas phase. Two commonly used matrix compounds are sho\ALJ:l�� "'- - -..... 0 HJCO r OH l o HO OCH3 9. Circle the compoun e that you would expect to absorb a lower wavelength of laser light. Explain your choice below. 10. Given what you know about the phase of matter involved in each of these techniques, draw lines showing which chromatography type would be most logically paired with which mass spectrometry ionization method.
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