Basically, you create acids here. And other stuff too i guess. Acidic Oxides: - SO2 / 2 SO2 - SO3 / 2 SO3 - 2 N2O3 - 2 N2O5 - 2 P2O3 - 2 P2O5 Acids: - H2SO3 - H2SO4 - 2 HNO2 - 2 HNO3 - 2 H3PO3 - 2 H3PO4 - H2S Oxygen Acids: Acidic Oxide + Water -> Acid