Chapter 15: IR Spectroscopy

Question 1

Bond: O-H & N-H

Answer 1

3400cm^-1

Question 2

Bond: C-H (sp)

Answer 2

3300cm-1

Question 3

Bond: C-H (sp²)

Answer 3

3100cm-1

Question 4

Bond: C-H (sp³)

Answer 4

2900cm-1

Question 5

Bond: aldehydic C-H

Answer 5

2700cm-1 and 2800cm-1

Question 6

Bond: C-C triple bond and C-N triple bond

Answer 6

2100cm-1

Question 7

Bond: C=O

Answer 7

1700cm-1

Question 8

Bond: C=C

Answer 8

1650cm-1

Question 9

Bond: aromatic C=C

Answer 9

1600cm-1 and 1500cm-1

Question 10

IR Spectroscopy is primarily used to:

Answer 10

characterize molecules by which functional groups they contain

Question 11

A molecular vibration must involve:

Answer 11

a change in the dipole moment in order to absorb appreciable amounts of IR light

Question 12

Stronger bonds require _____ frequencies of light.

Answer 12

higher

ex: sp C > sp² C > sp³ C
eg. C=O > C-O

Question 13

Lighter atoms require ______ frequencies of light

Answer 13

higher

ex: C-H > C-D > C-C > C-O