Question 1

Which of the following carbon-carbon bonds undergoes stretching at the highest frequency?

Accepted Answer

A)   sp3 C - sp3 C
B)   alkene sp2 C - sp2 C
C)   arene sp2 C - sp2 C
D)   CºCE) None of the above
F) B) and C)

Question 2

Provide a brief explanation to account for the observation that the frequency of the C=O stretching absorption in the infrared spectrum of 2-butanone is higher than that of 3-buten-2-one.

Accepted Answer

The C=O bond of 3-buten-2-one ...

Question 3

Which of the following bonds gives the weakest peak in the infrared spectrum for a stretching vibration?

Accepted Answer

A)   1
B)   2
C)   3
D)   4E) A) and B)
F) B) and D)

Question 4

Which of the following compounds gives an infrared spectrum with peaks in the ranges of 3200-3650 (strong, broad)  and 1600-1640 cm-1 (medium) ; but does not have peaks at 1630-1820 (strong) ? -1 (medium) ; but does not have peaks at 1630-1820 (strong) ?   A)  1 B)  2 C)  3 D)  4" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   1
B)   2
C)   3
D)   4E) A) and B)
F) A) and C)

Question 5

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C5H10O2)?

Accepted Answer

O-H: 3000-3600 cm^-1
C-...

Question 6

Which of the following compounds gives an infrared spectrum with peaks at 3000-3500 cm-1 and ~1750 cm-1? -1 and ~1750 cm-1?   A)  1 B)  2 C)  3 D)  4" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   1
B)   2
C)   3
D)   4E) B) and C)
F) A) and C)

Question 7

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C6H14O)?

Accepted Answer

O-H: ~3300 cm^-1
C-H: ~...

Question 8

Which of the following bonds gives rise to a strong, broad, absorbance at approximately 3200-3650 cm-1 in the infrared spectrum?

Accepted Answer

A)   C=O
B)   O-H
C)   C=C
D)   C-HE) B) and C)
F) None of the above

Question 9

Which of the following processes takes place upon absorption of infrared radiation?

Accepted Answer

A)   bond vibration
B)   electron excitation
C)   nuclear spin flip
D)   electron spin flipE) C) and D)
F) A) and B)

Question 10

Which of the following regions in the electromagnetic spectrum corresponds to the radiation with the longest wavelength?

Accepted Answer

A)   radio waves
B)   ultraviolet
C)   infrared
D)   visibleE) None of the above
F) All of the above

Question 11

Provide the structure of three compounds with the molecular formula C4H8O that give an absorption peak at 1600-1640 cm-1 in the infrared spectrum, but no significant peaks at 3000-3600 cm-1 or at 1650-1750 cm-1.

Accepted Answer

Any three ...

Question 12

Which of the following functional groups is likely to be present in a molecule that has peaks in the infrared spectrum at 1000-1250 cm-1 (strong) , but does not have peaks 3200-3650 at 1630-1820 or cm-1?

Accepted Answer

A)   alcohol
B)   aldehyde or ketone
C)   ether
D)   esterE) A) and B)
F) A) and C)

Question 13

What are the units of wavenumber, -1 C)  J*mol-1 D)  none, wavenumber is a dimensionless quantity" class="answers-bank-image d-inline" rel="preload" > , in infrared spectroscopy?

Accepted Answer

A)   cm
B)   cm-1
C)   J*mol-1
D)   none, wavenumber is a dimensionless quantityE) All of the above
F) B) and D)

Question 14

Provide a brief explanation to account for the observation that the frequency of the C=O stretching absorption in the infrared spectrum of N,N-dimethylacetamide, CH3CON(CH3)2, is higher than that of methyl acetate, CH3CO2CH3.

Accepted Answer

The C=O bond of the amide is weaker than that of the ester. Nitrogen is less electronegative than oxygen, and therefore a better electron pair donor. Accordingly, the resonance contributor in which the nitrogen has donated a pair of electrons to the carbonyl carbon atom is an important contributor to the structure.

Question 15

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C4H9NO)?

Accepted Answer

N-H: ~3500 cm^-1
C-H: ...

Question 16

Which of the following compounds gives an infrared spectrum with no significant peaks at ~3300 cm-1 or 1600-1680 cm-1? -1 or 1600-1680 cm-1?   A)  1 B)  2 C)  3 D)  4" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   1
B)   2
C)   3
D)   4E) All of the above
F) A) and B) B

Question 17

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm-1 (sharp peak)  and 2150 cm-1 (sharp peak) ? -1 (sharp peak)  and 2150 cm-1 (sharp peak) ?   A)  1 B)  2 C)  3 D)  4" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   1
B)   2
C)   3
D)   4E) B) and D)
F) All of the above

Question 18

Which of the following compounds gives a carbonyl bond absorption at the lowest frequency?

Accepted Answer

A)   1
B)   2
C)   3
D)   4E) None of the above
F) All of the above

Question 19

What range of wavelengths corresponds to the infrared region of the electromagnetic spectrum?

Accepted Answer

A)   200-400 nm
B)   400-700 nm
C)   2.5-50 mm
D)   2-10 mmE) A) and D)
F) B) and D)

Question 20

Which of the following functional groups is likely to be present in a molecule that has peaks in the infrared spectrum at 1630-1820 cm-1 (strong, broad)  and 1000-1250 cm-1; but does not have peaks at 3200-3650 cm-1?

Accepted Answer

A)   alcohol
B)   aldehyde or ketone
C)   ether
D)   esterE) None of the above
F) B) and C) D

Exam 12: Infrared Spectroscopy

Which of the following carbon-carbon bonds undergoes stretching at the highest frequency?

Correct Answer
verified

Provide a brief explanation to account for the observation that the frequency of the C=O stretching absorption in the infrared spectrum of 2-butanone is higher than that of 3-buten-2-one.

Correct Answer
verified
The C=O bond of 3-buten-2-one ...
View Answer

Which of the following bonds gives the weakest peak in the infrared spectrum for a stretching vibration?

Correct Answer
verified

Which of the following compounds gives an infrared spectrum with peaks in the ranges of 3200-3650 (strong, broad) and 1600-1640 cm^-1 (medium) ; but does not have peaks at 1630-1820 (strong) ?

Correct Answer
verified

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C₅H₁₀O₂)?

Correct Answer
verified
O-H: 3000-3600 cm^-1
C-...
View Answer

Which of the following compounds gives an infrared spectrum with peaks at 3000-3500 cm^-1 and ~1750 cm^-1?

Correct Answer
verified

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C₆H₁₄O)?

Correct Answer
verified
O-H: ~3300 cm^-1
C-H: ~...
View Answer

Which of the following bonds gives rise to a strong, broad, absorbance at approximately 3200-3650 cm^-1 in the infrared spectrum?

Correct Answer
verified

Which of the following processes takes place upon absorption of infrared radiation?

Correct Answer
verified

Which of the following regions in the electromagnetic spectrum corresponds to the radiation with the longest wavelength?

Correct Answer
verified

Provide the structure of three compounds with the molecular formula C₄H₈O that give an absorption peak at 1600-1640 cm^-1 in the infrared spectrum, but no significant peaks at 3000-3600 cm^-1 or at 1650-1750 cm^-1.

Correct Answer
verified
Any three ...
View Answer

Which of the following functional groups is likely to be present in a molecule that has peaks in the infrared spectrum at 1000-1250 cm^-1 (strong) , but does not have peaks 3200-3650 at 1630-1820 or cm^-1?

Correct Answer
verified

What are the units of wavenumber, , in infrared spectroscopy?

Correct Answer
verified

Provide a brief explanation to account for the observation that the frequency of the C=O stretching absorption in the infrared spectrum of N,N-dimethylacetamide, CH₃CON(CH₃)₂, is higher than that of methyl acetate, CH₃CO₂CH₃.

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C₄H₉NO)?

Correct Answer
verified
N-H: ~3500 cm^-1
C-H: ...
View Answer

Which of the following compounds gives an infrared spectrum with no significant peaks at ~3300 cm^-1 or 1600-1680 cm^-1?

Correct Answer
verified
B

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm^-1 (sharp peak) and 2150 cm^-1 (sharp peak) ?

Correct Answer
verified

Which of the following compounds gives a carbonyl bond absorption at the lowest frequency?

Correct Answer
verified

What range of wavelengths corresponds to the infrared region of the electromagnetic spectrum?

Correct Answer
verified

Which of the following functional groups is likely to be present in a molecule that has peaks in the infrared spectrum at 1630-1820 cm^-1 (strong, broad) and 1000-1250 cm^-1; but does not have peaks at 3200-3650 cm^-1?

Correct Answer
verified
D

Exam 12: Infrared Spectroscopy

Which of the following carbon-carbon bonds undergoes stretching at the highest frequency?

Correct AnswerverifiedShow Answer

Provide a brief explanation to account for the observation that the frequency of the C=O stretching absorption in the infrared spectrum of 2-butanone is higher than that of 3-buten-2-one.

Correct AnswerverifiedThe C=O bond of 3-buten-2-one ...View AnswerShow Answer

Which of the following bonds gives the weakest peak in the infrared spectrum for a stretching vibration?

Correct AnswerverifiedShow Answer

Which of the following compounds gives an infrared spectrum with peaks in the ranges of 3200-3650 (strong, broad) and 1600-1640 cm-1 (medium) ; but does not have peaks at 1630-1820 (strong) ?

Correct AnswerverifiedShow Answer

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C5H10O2)?

Correct AnswerverifiedO-H: 3000-3600 cm-1C-...View AnswerShow Answer

Which of the following compounds gives an infrared spectrum with peaks at 3000-3500 cm-1 and ~1750 cm-1?

Correct AnswerverifiedShow Answer

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C6H14O)?

Correct AnswerverifiedO-H: ~3300 cm-1C-H: ~...View AnswerShow Answer

Which of the following bonds gives rise to a strong, broad, absorbance at approximately 3200-3650 cm-1 in the infrared spectrum?

Correct AnswerverifiedShow Answer

Which of the following processes takes place upon absorption of infrared radiation?

Correct AnswerverifiedShow Answer

Which of the following regions in the electromagnetic spectrum corresponds to the radiation with the longest wavelength?

Correct AnswerverifiedShow Answer

Provide the structure of three compounds with the molecular formula C4H8O that give an absorption peak at 1600-1640 cm-1 in the infrared spectrum, but no significant peaks at 3000-3600 cm-1 or at 1650-1750 cm-1.

Correct AnswerverifiedAny three ...View AnswerShow Answer

Which of the following functional groups is likely to be present in a molecule that has peaks in the infrared spectrum at 1000-1250 cm-1 (strong) , but does not have peaks 3200-3650 at 1630-1820 or cm-1?

Correct AnswerverifiedShow Answer

What are the units of wavenumber, , in infrared spectroscopy?

Correct AnswerverifiedShow Answer

Provide a brief explanation to account for the observation that the frequency of the C=O stretching absorption in the infrared spectrum of N,N-dimethylacetamide, CH3CON(CH3)2, is higher than that of methyl acetate, CH3CO2CH3.

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C4H9NO)?

Correct Answerverified N-H: ~3500 cm-1C-H: ...View AnswerShow Answer

Which of the following compounds gives an infrared spectrum with no significant peaks at ~3300 cm-1 or 1600-1680 cm-1?

Correct AnswerverifiedB

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm-1 (sharp peak) and 2150 cm-1 (sharp peak) ?

Correct AnswerverifiedShow Answer

Which of the following compounds gives a carbonyl bond absorption at the lowest frequency?

Correct AnswerverifiedShow Answer

What range of wavelengths corresponds to the infrared region of the electromagnetic spectrum?

Correct AnswerverifiedShow Answer

Which of the following functional groups is likely to be present in a molecule that has peaks in the infrared spectrum at 1630-1820 cm-1 (strong, broad) and 1000-1250 cm-1; but does not have peaks at 3200-3650 cm-1?

Correct AnswerverifiedD

Correct Answer
verified

Correct Answer
verified
The C=O bond of 3-buten-2-one ...
View Answer

Correct Answer
verified

Which of the following compounds gives an infrared spectrum with peaks in the ranges of 3200-3650 (strong, broad) and 1600-1640 cm^-1 (medium) ; but does not have peaks at 1630-1820 (strong) ?

Correct Answer
verified

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C₅H₁₀O₂)?

Correct Answer
verified
O-H: 3000-3600 cm^-1
C-...
View Answer

Which of the following compounds gives an infrared spectrum with peaks at 3000-3500 cm^-1 and ~1750 cm^-1?

Correct Answer
verified

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C₆H₁₄O)?

Correct Answer
verified
O-H: ~3300 cm^-1
C-H: ~...
View Answer

Which of the following bonds gives rise to a strong, broad, absorbance at approximately 3200-3650 cm^-1 in the infrared spectrum?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Provide the structure of three compounds with the molecular formula C₄H₈O that give an absorption peak at 1600-1640 cm^-1 in the infrared spectrum, but no significant peaks at 3000-3600 cm^-1 or at 1650-1750 cm^-1.

Correct Answer
verified
Any three ...
View Answer

Which of the following functional groups is likely to be present in a molecule that has peaks in the infrared spectrum at 1000-1250 cm^-1 (strong) , but does not have peaks 3200-3650 at 1630-1820 or cm^-1?

Correct Answer
verified

Correct Answer
verified

Provide a brief explanation to account for the observation that the frequency of the C=O stretching absorption in the infrared spectrum of N,N-dimethylacetamide, CH₃CON(CH₃)₂, is higher than that of methyl acetate, CH₃CO₂CH₃.

Label three peaks in the following spectrum with the bond that gives rise to them, and identify the functional group that is present in the compound (the compound has a formula of C₄H₉NO)?

Correct Answer
verified
N-H: ~3500 cm^-1
C-H: ...
View Answer

Which of the following compounds gives an infrared spectrum with no significant peaks at ~3300 cm^-1 or 1600-1680 cm^-1?

Correct Answer
verified
B

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm^-1 (sharp peak) and 2150 cm^-1 (sharp peak) ?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Which of the following functional groups is likely to be present in a molecule that has peaks in the infrared spectrum at 1630-1820 cm^-1 (strong, broad) and 1000-1250 cm^-1; but does not have peaks at 3200-3650 cm^-1?

Correct Answer
verified
D