Radial: A word with diverse meanings in medicine and the biomedical sciences: 1  Pertaining to the radius, the smaller bone in the forearm. 2  The radial artery is so named because of its proximity to the radius. 3  Pertaining to the radius of a circle.
A 3D model of ethyne (acetylene), the simplest alkyne. In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbonâcarbon triple bond. The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series with the general chemical formula CnH2nâ2.
In acetylene, the HâCâ¡C bond angles are 180Â°. By virtue of this bond angle, alkynes are rod-like. Correspondingly, cyclic alkynes are rare. Benzyne is highly unstable. The Câ¡C bond distance of 121 picometers is much shorter than the C=C distance in alkenes (134 pm) or the CâC bond in alkanes (153 pm).