H-: H-CI: HBr: H一 Acidic Acidic Acidic Acidic 6 Acidic HgC H3C-C" H3C-N: Acidic :O-H :N-H Carboxylic acid H Acidic Amine Amide Acidic Acidic Alcohol Phenol Fig.3.Acidic protons in mineral acids and common functional groups