Salt Analysis

Concept:The Griess–Ilosvay test detects nitrite ions ($\mathrm{NO}_2^-$) by diazotization followed by coupling to form a coloured azo dye.Explanation:In acidic medium, nitrite ion generates nitrous acid ($\mathrm{HNO}_2$).Nitrous acid diazotizes sulphanilic acid to give a diazonium salt.This diazonium salt couples with $\alpha$-naphthylamine to produce a reddish-pink azo dye.Statement I correctly lists the reagents: sulphanilic acid and $\alpha$-naphthylamine.Statement II correctly describes the diazotization of sulphanilic acid by acidified nitrite and subsequent coupling to form an azo dye.Both statements are accurate.Answer:Both Statement I and Statement II are true. Option D.