IR PRACTICE ACTIVITY
You may work in pairs. Be sure to put both names on the top of this sheet and hand it in when
you are done.
Directions:
From the spectrum and the IR peak location index:
1) Characterize the major peaks.
2) Identify possible functional groups and list them.
3) Identify the structure from the list of possibilities.
4) Write the structure and the name of the molecule next to the spectrum.
The first one is done for you.
1.
.
2.
3.
4.
5.
Please do not write on this sheet, and hand it in when you are finished with the worksheet.
List of possible structures:
3-pentanone
propanoic acid
1-hexene
OH
O
O
Cyclooctanol
1,7-octadiyne
OH
IR PRACTICE ACTIVITY
TEACHER NOTES
Answers:
1. 3000 cm-1
strong broad
-OH group
alcohol
1715 cm-1
strong narrow
C=O group
ketone or aldehyde
propanoic acid
2. 3300 cm-1
strong broad
-OH group
2900 cm-1
strong narrow
C-C-H group
cyclooctanol
| |
alcohol
C-C
cyclic alkane
3. 2900 cm-1
strong narrow
C-H group
alkane
1700 cm-1
strong narrow
C = O group
ketone or aldehyde
4. 3100 cm-1
weak narrow
C=C-H
alkene
2900 cm-1
strong narrow
C-H
alkane
1650 cm-1
strong narrow
C=C-H
alkene
1-hexene
5. 3300 cm-1
strong narrow
CC-H
alkyne
2900 cm-1
strong narrow
C-H
alkane
2100 cm-1
weak narrow
CC-H
alkyne
1,7- octadiyne
Last updated 8-01
3-pentanone