1.) Explain the difference in the C=O stretches in 2-naphthaldehyde and benzophenone.
2.) Based on what you know about vibrational frequencies, would you expect cyclohexanecarbaldehyde or benzaldehyde to have a higher C=O stretch?
3.) Would the presence of a nitro group in the 4- and 4'- positions in benzophenone increase the frequency of the carbonyl stretch or decrease it? Explain using resonance structures.