Chapter 11 INFRARED SPECTROSCOPY

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Chapter 11INFRARED SPECTROSCOPY
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Assignment for Chapter 11

• Skip Section 11.17
• Summary
• Skip Section 11.1
• Problems (next slide)
• Section 11.2
• Sections 11.3 through 11.16

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Problem Assignment

• In-Text Problems
• 11-4 through 11-6
• 11-9 through 11-17
• End-of-Chapter Problems
• 18
• 20 through 23
• 27 (mono-substituted benzene ring)

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Sect. 11.2 Index of Hydrogen Deficiency

• Compare actual formula with calculated formula
  for an acyclic, saturated analog
• Difference in Hs/2 index of H-deficiency
• Gives the number of double or triple bonds or
  rings in a molecule
• If index 4 or more, expect the presence of a
  benzenoid ring

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Index of hydrogen deficiency

• O or S -- doesnt change calculated formula
• N or P -- add one to the calculated formula
• F, Cl, Br, I -- substract one from calculated
  formula

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The Electromagnetic Spectrum
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Infrared Spectrometer
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4-Methyl-2-pentanoneC-H lt 3000, CO _at_ 1715 cm-1
C-H stretch
CO stretch
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Molecular vibrations

• Section 11-5 describes these, but IR-Tutor
  available in CB 280 is great!
• Basically two types
• stretching vibrations
• bending vibrations

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IR TUTOR

• Select Chemistry Applications icon
• Select Structure Drawing icon
• Select Spectroscopy icon
• Select IR Tutor icon

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