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9 Cards in this Set
- Front
- Back
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Which band would be expected in the IR spectrum of an ester?
a) 1600 b) 1670 c) 1740 d) 2200 e) 3500 |
c) 1740
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What two things RAISE c=o freq's in IR spectrums?
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-placement in a ring system: 6 membered ring or 5 membered ring (~1725)
-bond to O (ester) (~1735) |
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What two things LOWER c=o stretching freq's?
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-conjugation, seperated double bonds by singe bond (~1680)
-bond to a N (amide) (~1650) |
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What does IR spectroscopy cause molecules to do?
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to vibrate
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Why use IR spectroscopy?
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used to find out what TYPES OF BONDS exist in a molecule
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What are the three IR freq's to know?
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O-H 3500
C-H 3000 C=O 1700 |
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Sp2 vs Sp3 C-H bonds, what are they're IR freq's?
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Sp2: higher than 3000
Sp3: lower than 3000 |
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Alkynes show up at what IR freq?
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-2200
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Why only terminal alkynes show signal?
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IR absorbance for any bond is proportional to the polarity of the bond. O=C=O is non-polar.
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