It is an unstable liquid which boils at 33.5° C., and on heating rapidly polymerizes to dipentene, the same change being effected by hydrochloric acid.
Ethane, when heated to this degree, splits up into ethylene and hydrogen, whilst ethylene decomposes to methane and acetylene, and the acetylene at once polymerizes to benzene, styrolene, retene, &c. A portion also condenses, and at the same time loses some hydrogen, becoming naphthalene; and the compounds so formed by interactions amongst themselves build up the remainder of the hydrocarbons present in the coal tar, whilst the organic substances containing oxygen in the coal break down, and cause the formation of the phenols in the tar.
It is a liquid which boils at 41° C. It rapidly polymerizes to di-cyclo-pentadiene.
At ordinary temperatures it rapidly polymerizes (probably to a tetramethylcylobutanedione).
It polymerizes, giving isodibutylene, C 8 H 16, and isotributylene, C12H24, liquids which boil at 110-113° and 178-181° C. Amylene, C5H10, exists in five isomeric forms, viz.