Question 5. IR analysis of an amide, ketone, and acid chloride reveals CO stretching frequencies of (on average) 1680 1720, and 1800 cm, respectively. R1 NRC 1680 RR 1720 Veo 1800 One could explain the difference between the amide and acid chloride based on resonance, but that argument fails to explain the fact that the ketone falls between the two a. Provide an explanation for the unusually high stretching frequency for the carbonyl in the acid chloride that is not based on resonance. [4 pts] b. Use an illustration of the orbitals involved to help support your answer. [2 pts]