The IR spectrum of propanoic acid (Fig. 2.17) indicates that the absorption for the O-H stretch of the carboxylic acid functional group is due to a hydrogen-bonded form. Draw the structure of two propanoic acid molecules showing how they could dimerize via hydrogen bonding.
In Figure 2.17

Transcribed Image Text:

100 90 80 70 60 50 LIaliphatic aromatic aromatic C-H combination (stretch) (Stretch band (wag) primary N-H 40 (asym. and sym. stretch) C-N stretch) 30 20 10 CH3 CC (ring stretch) N-H (bend) L-」 C-H out-of-plane bend) 0 4000 3600 3200 2800 2400 2000 1800 1600 1400 1200 1000 800 650 Wavenumber (cm-1)