1. Nitration with Dilute Nitric Acid (dil. HNO3)



Reaction: Phenol reacts with dilute HNO3 at a low temperature.



Products: Forms a mixture of ortho-nitrophenol and para-nitrophenol.



Key Concept: The hydroxyl group (-OH) is a strong activating group that directs incoming groups to the ortho and para positions.



2. Nitration with Concentrated Nitric Acid ( conc. HNO3)



Reaction: Phenol reacts vigorously with concentrated HNO3.



Products: Forms 2,4,6-trinitrophenol, commonly known as ...