4.8 Infrared Spectroscopy Problems
- Page ID
- 432185
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After completing this section, you should be able to
- determine functional groups in an IR spectrum
Here are some problems for IR analysis.
What functional group is present in the spectrum below?
- Answer
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Alkyne
What functional group is present in the spectrum below?
- Answer
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Carboxylic Acid
Which IR spectrum goes with which molecule below?
Molecule A: 
Molecule B: 
IR spectrum 1:
IR spectrum 2:
- Answer
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Molecule A is Spectrum 2.
Molecule B is Spectrum 1.
What notable peaks in the IR spectrum verify that benzaldehyde is present?
- Answer
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Frequency (cm-1) Functional Group 3063 Csp2-H 2818 and 2736 aldehyldic proton 1695 C=O 1653-1455 aromatic ring