An organic compound ' A ' burns with a sooty flame. It is negative towards Tollen's reagent test and positive for Borsche's reagent test. The compound ' A ' is

Step-by-step solution

Since given compound 'A' burns with sooty flame, therefore it must be an aromatic compound. Again when it reacts with Borsche's reagent (acidic 2, 4-dinitrophenyl hydrazine solution), it yields orange precipitate. Therefore it must be a carbonyl compound, i.e., aldehyde, or ketone. But 'A' does not perform Tollen's reagent test therefore, it must be an aromatic ketone. Hence, 'A' is acetophenone.