Increased single-bond character in a carbonyl group is associated with a decreased carbonoxygen stretching frequency. Among the

Question:

Increased “single-bond character” in a carbonyl group is associated with a decreased carbon–oxygen stretching frequency. Among the three compounds benzaldehyde, 2,4,6-trimethoxybenzaldehyde, and 2, 4, 6-trinitrobenzaldehyde, which one will have the lowest frequency carbonyl absorption? Which one will have the highest?