15. Analytical Techniques:IR, NMR, Mass Spect

Identify the hydrocarbon that has a molecular ion with an m/z value of 128, a base peak with an m/z value of 43, and significant peaks with m/z values of 57, 71, and 85.

Can one of the possible molecular formulas contain a nitrogen atom?

Suggest possible molecular formulas for a compound that has a molecular ion with an m/z value of 86.

Determine the molecular formula for each of the following:

b. a compound that contains C, H, and one O and has a molecular ion with an m/z value of 100

Suppose we have some optically pure (R)-2-butyl acetate that has been 'labeled' with the heavy ¹⁸O isotope at one oxygen atom as shown.

(c) Explain how you would prove experimentally where the ¹⁸O label appears in the products. (¹⁸O is not radioactive.)

What is the most likely m/z value for the base peak in the mass spectrum of 3-methylpentane?

Can a high-resolution mass spectrometer distinguish between them?

The IR and mass spectra for three different compounds are shown below. Identify each compound.

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