Which of the following is not a chromophore

Question

Which of the following is not a chromophore (A) -N=N- (B) -NO (C) -NO2 (D) -NH2

Tardigrade Admin · Accepted Answer

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

- O H, - COO H, - S O_{3} H, - N H_{2}, - N H R, - N R_{2}

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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 (anilineyellow) is a dye.
Solution

Q. Which of the following is not a chromophore

$- N = N -$

$- NO$

$- N O_{2}$

$- N H_{2}$

Q. Which of the following is not a chromophore

−N=N−

−NO

−NO2​

−NH2​

$- N = N -$

$- NO$

$- N O_{2}$

$- N H_{2}$