1) Benzeneazobenzene 
Azobenzene is a chemical compound composed of two phenyl rings linked by a N=N double bond. It is the simplest example of an azo compound. The term `azobenzene` or simply `azo` is often used to refer to a wide class of molecules that share the core azobenzene structure, with different chemical functional groups extending from the phenyl rings....
• (n.) A substance (C6H5.N2.C6H5) derived from nitrobenzene, forming orange red crystals which are easily fusible.
(from the article `azo compound`) Most aromatic azo compounds are prepared by the reaction of a diazonium salt with an organic substance that contains easily replaced hydrogen atoms. ...
<chemistry> A substance (C6H5.N2.C6H5) derived from nitrobenzene, forming orange red crystals which are easily fusible. ... (11 Mar 1998) ... 
Az`o·ben'zene noun [ Azo- + benzene .] (Chemistry) A substance (C 6 H 5 .N 2 .C 6 H 5 ) derived from nitrobenzene, forming orange red crystals which are easily fusible. 
Azobenzene is a yellow or orange crystalline solid used mainly in the manufacture of dyes. It has the formula C6H5N:NC6H5.
Red insoluble crystalline powder. Symbol C12H10N2
an orange-red, crystalline, water-insoluble powder, CHN, obtained from nitrobenzene by reduction: used chiefly in the manufacture of dyes and as an insecticide. Also called