can benzoic acid and phenol is distinguished by azo dye test

Yes phenol and benzoic acid can be distinguished by azo dye test,as phenol will give azo dye test but benzoic acid cannot. In weakly alkaline medium, phenol reacts with benzenediazonium chloride to form colored substances which are called as azo dyes. The reaction takes place at 273-278 K temperature and also known as coupling reaction. Thanks & regards Aarti Gupta askiitians faculty