Physical properties

The physical properties of alkyl halides differ considerably from those of the alkanes they are derived from, once a hydrogen is replaced by a halogen. This section develops the reasons for that difference along three threads taken up one at a time: the nature of the intermolecular forces acting between alkyl halide molecules, which follows from the polarity of the C-X bond (10.4.1); how the boiling point of a series of alkyl halides changes with the identity of the halogen, with the length of the carbon chain, and with the degree of branching (10.4.2); and the solubility behaviour of both alkyl and aryl halides in water versus in organic solvents, including why isomeric dihalobenzenes have similar boiling points but quite different melting points (10.4.3). Throughout, the boiling poi …