Operating Procedures for Chemicals Acetic Acid Ammonium Sulfide Chrome Etchant Citric:H2O2 Citric:H3PO4:H2O2:H2O Copper Etchant H2SO4:H2O2:H2O H3PO4:H2O2:H2O Hydrochloric Acid Hydrofluoric Acid Hydrogen Peroxide NH4OH:H2O2:H2O Nitric Acid Phosphoric Acid Potassium Hydroxide, Heated Potassium Hydroxide, Room Temperature Purestrip