Which of the following is not a chromophore

Step-by-step solution

A dye molecule is made up of two different part (i) Chromophore (ii) Auxochrome. The groups which produce colour in a compound i.e., chromophores are usual unsaturated groups like nitro, nitroso, azo, azoxy, carbonyl and olefinic bonds Auxochrome are usually acidic / basic functional group like - OH , - COOH , - SO 3 H , - NH 2 , - NHR , - NR 2 . A compound containing only a chromophore may be coloured material but not a dye. For example azo benzene is red coloured but not a dye. Where as para amino azobenzene (ani