Outline Answers

For CH2=CH-NMe3, the nitrogen atom bearing the positive charge has eight valence electrons. It cannot expand its valence electrons to ten, and hence an alternative resonance structure cannot be drawn. 

On deprotonation of cycloheptatriene, an anion with eight Tt-electrons is formed. This anion is not stabilised by aromaticity, hence the high pAi,-value of cycloheptatriene. 

On protonation of guanidine, the (H2N)2C=NH+ cation is stabilised by extensive delocalisation of the charge by the electron-donating NH2 (+M) groups (see below). 

The electron-donating propyl group (+1) in 1-aminopropane will help increase the basicity. 

For aniline, the lone pair on nitrogen can be delocalised onto the benzene ring, which will help decrease the basicity (i.e. the benzene ring helps tie up the lone pair, making it less basic). On protonation of aniline, the positive charge cannot be stabilised by delocalisation. 

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Outline answers to each of these questions will be given here and detailed dicussions will follow in later sections. 

Instructor s Manual/Test Item File Written by the authors, this manual is designed to help instructors plan and prepare for classes using Biochemistry The Molecular Basis of Life. For each chapter in the text, this manual provides a chapter outline and an extended lecture outline. Answers for the even-numbered questions appear at the end of each part. The test item file contains approximately thirty-five multiple choice and critical thinking problems per chapter. 

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