question_answer

Azo-dyes are prepared from :    [BHU 2004; Pb. CET 2001]

A)                 Aniline 

B)                 Salicylic acid

C)                 Benzaldehyde  

D)                 Chlorobenzene

Correct Answer: A

Solution :

           When aniline is treated with \[HN{{O}_{2}}\] at 0?5°C then diazonium salt is formed and by the coupling of diazonium salt and phenol azo dyes are prepared.