Chapter 12

Question 1

Infrared spectrometer

Answer 1

Measures a compounds absorption of infrared light as a function of frequency or wavelength.

Question 2

Carbon-carbon bond stretching frequencies

Answer 2

C-C 1200cm^-1

C=C 1660cm^-1

C triple bond C <2200cm^-1

Question 3

Frequencies of Alkynes

Answer 3

The carbon carbon triple bond absorb infrared light at higher frequencies than CC single or double bonds. Most alkyne triple bonds have a stretching frequency between 2100 and 2200 cm^-1.

Question 4

Carbon-hydrogen bond stretching

Answer 4

Alkanes, alkenes, and alkynes have C-H stretching frequencies.

C-H bonds involving sp3 hybrid carbon atoms typically absorb at frequencies to the right of 3000cm^-1.

Those involving sp2 hybrid carbon atoms absorb to the left of 3000cm^-1.

Question 5

Alcohol Stretching Frequency

Answer 5

-OH has a frequency around 3300cm^-1

Question 6

Acid Frequency

Answer 6

3000cm-1

Question 7

Amine Frequency

Answer 7

N-H 3300cm^-1, broad with spike.

Question 8

Carbon Oxygen bond frequency

Answer 8

C-O bonds (typically alcohols and ethers) show a strong absorption between 1000 to 1200cm^-1.