L3 Rich: IR spectroscopy part 2

Question 1

what affects the position of bands in the IR spectrum?

Answer 1

mass of the atoms

strength of the bond

Question 2

stronger the bond the ____ the _____

Answer 2

higher the frequency

Question 3

the bigger the molecules the more?

Answer 3

complex the IR spectrum

Question 4

what do we to do when we have large molecules?

Answer 4

do not try and assign specific vibrational modes

Question 5

What to think when looking at IR of large molecules?

Answer 5

think of one or two bonds that are moving

Question 6

what is key when looking at a large molecules IR spectrum?

Answer 6

Assign functional groups to specific frequencies

Question 7

what region is looked at first when interpreting IR spectra?

Answer 7

the higher regions

1600+

Question 8

what kind of peak is N-H?

Answer 8

sharp

Question 9

what kind of peak is O-H?

Answer 9

It is broad (usually)

Question 10

whats the lower region or IR and whats it also known as?

Answer 10

400 - 1600

fingerprint region

Question 11

what peaks can sometimes be found in the fingerprint region?

Answer 11

c-cl

c-f

Question 12

what number in the IR spectra shows a bond to hydrogen?

Answer 12

2500+

Question 13

what happens when the mass is low?

Answer 13

vibrational frequency is high

Question 14

what is the triple bond region?

Answer 14

2000- 2500

Question 15

what region doesn’t usually have peaks and why?

Answer 15

2000-2500
the triple bond
as its uncommon

Question 16

Name two triple bonds?

Answer 16

C—N

C—C

Question 17

what stem double bond region?

Answer 17

1500- 2000

Question 18

Name two double bonds?

Answer 18

C–O

C–N

Question 19

which double bond peak has more intensity, C – O or C– N?

Answer 19

C – O

Question 20

where’s the single bond region?

Answer 20

500 - 1500

Question 21

what dominates the single bond region?

Answer 21

C-C
C-O
C-CL

Question 22

Which single bond peak is intense?

Answer 22

C-CL

Question 23

what do you need to do if you suspect theirs inorganic molecules?

Answer 23

look at an inorganic table provided

Question 24

what do you need for an IR peak to be present?

Answer 24

covalent bond

Question 25

what pea is usually at 2900?

Answer 25

C-H