Copper Bath

A solution of copper used for depositing the metal in the electroplating proce . For some metals, such as zinc or iron, which decompose copper sulphate solution, special baths have to be used. The regular bath for copper plating is the following: To water acidulated with 8 to 10 percent. of sulphuric acid as much copper sulphate is added as it will take up at the ordinary temperature. The saturated bath should have a density of 1.21. It is used cold and is kept in condition by the use of copper anodes, or fresh crystals may be added from time to time. For deposition on zinc, iron, tin and other metals more electropositive than copper, the following baths may be used, expre ed in parts by weight: Tin Iron and Steel.   Cast Iron Cold     Hot.     and Zinc.   Zinc. Sodium Bisulphate,    500 200 300      100 Pota ium Cyanide,    500 700 500      700 Sodium Carbonate,    1000 500 ---      --- Copper Acetate, 475 500 350      450 Aqua Ammoniae, 350 300 200      150 Water, 2500    2500 2500     2500 These are due to Roseleur. 153  STANDARD ELECTRICAL DICTIONARY.