Chemistry - AMINES Question with Solution | TestHub
Statement-1: Aniline on reaction with at followed by coupling with -naphthol gives a dark blue coloured precipitate.
and
Statement-2 : The colour of the compound formed in the reaction of aniline with NaNO2 / HCl at 0° followed by coupling with b-naphthol is due to the extended conjugation.
Options:
Answer:
Solution:
Question Explanation:
The question presents two statements regarding the reaction of aniline followed by coupling with dimethylaniline and asks to determine the truth of each statement and whether Statement-2 correctly explains Statement-1.
Concept:
This question is based on
1. Diazotization,
2. Azo Coupling Reaction,
3. Extended Conjugation
Solution:
Statement-1 is False. Aniline reacts with NaNO2 + HCl to form benzenediazonium chloride. This ion then undergoes azo coupling with N,N-dimethylaniline to form bright yellow dye. Statement-2 is also True. The yellow colour of the azo dye is due to the presence of the azo group and the extended conjugation of the pi-electron system which absorbs visible light. Statement-2 correctly explains the colour described in Statement-1.
Final Answer: Option (D)
