The chemical reactions and pathways involving n-octane, the 8 carbon straight chain alkane used in organic syntheses, calibrations, and azeotropic distillations. It is a common component of gasoline and other petroleum products and the engine fuel antiknocking properties of an isomer of n-octane are used as a comparative standard in the Octane Rating System. [ http://eawag-bbd.ethz.ch/oct/oct_map.html ]