alleryPhenol heated with phthalic anhydride and conc. H2SO4 gives which dye?
AMethyl orange
BFluorescein
CCongo red
DPhenolphthalein
Answer & Solution
Correct answer: D. Phenolphthalein
Phenol condenses with phthalic anhydride to give phenolphthalein, which is dark pink in NaOH.
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