Problem 1
Draw structures of the following cycloalkanes: (a) cyclobutane; (b) cycloheptane; (c) methylcyclopentane; (d) 1,4 -dimethylcyclohexane; (e) 1 -ethyl-3-propylcyclooctane.
Problem 4
Give names and structures for isomers of dimethylcyclobutane.
Problem 6
Discuss ring strain with reference to cycloalkanes \(\mathrm{C}_{n} \mathrm{H}_{2 n}\) for \(3 \leq n \leq 8\).
Problem 7
The standard enthalpy of combustion for \(\mathrm{C}_{3} \mathrm{H}_{6}(\mathrm{g})\) at \(298 \mathrm{K}\) is \(-2091 \mathrm{kJ} \mathrm{mol}^{-1}\). Determine \(\Delta_{\mathrm{f}} H^{\mathrm{o}}\left(\mathrm{C}_{3} \mathrm{H}_{6}\right.\) g). Other data: \(\Delta_{\mathrm{f}} H^{\circ}\left(\mathrm{CO}_{2}, \mathrm{g}\right)\) and \(\Delta_{\mathrm{f}} H^{\circ}\left(\mathrm{H}_{2} \mathrm{O}, 1\right)=\) -394 and \(-286 \mathrm{kJ} \mathrm{mol}^{-1}\) respectively.
Problem 8
When fully combusted, an acyclic alkane A gives \(13.20 \mathrm{g} \mathrm{CO}_{2}\) and \(6.306 \mathrm{g} \mathrm{H}_{2} \mathrm{O} .\) Suggest a possible identity for \(\mathbf{A}\).
Problem 10
Distinguish between initiation, propagation and termination steps in a radical chain reaction and gives examples of each.
Problem 11
Outline the steps involved in the reaction of \(\mathrm{Cl}_{2}\) with butane to give monochlorinated products. Comment on factors that affect the product distribution.
Problem 12
How would \(^{1} \mathrm{H}\) NMR spectroscopy allow you to distinguish between the products of the monochlorination of 2 -methylpropane?
Problem 14
The reaction of \(\mathrm{Cl}_{2}\) with propane gives \(55 \%\) 2-chloropropane and \(45 \%\) 1-chloropropane. In our discussion, we rationalized the product distribution in terms of the relative stabilities of the intermediate alkyl radicals. (a) Are the statistics of abstracting \(\mathrm{H}^{*}\) from a primary versus secondary \(\mathrm{C}\) atom in propane also consistent with the observed product distribution? (b) What can you say about the relative rates of formation of the two alkyl radical intermediates?
Problem 15
Why do you think that \(\mathrm{O}_{2}\) has a dramatic effect on many radical reactions?
