i.            Suggest a possible structure for the hydrocarbon C₆H₁₄, which has the infrared spectrum shown here: Is there more than one correct structure?

ii.            The hydroxylamine I can be oxidized by MnO₂ to the amide oxohaemanthidine (II). In dilute solution, the carbonyl absorption band of II occurs at 1702 cm^–1 . Explain this observation.

a.       

iii.            The infrared spectra of the three xylene (dimethylbenzene) isomers, and an additional aromatic hydrocarbon, are given below. Assign the spectra to the isomers and suggest a potential structure for the remaining unknown substance.

iv.            The COH stretching mode of chloroform (CHCl₃), which occurs at 3022 cm^–1 , is one of the rare exceptions to the 3000-cm^–1 rule. What is the rule? Suggest an explanation for this exception.