studing the stability of copper (CuCl2), ammonium hydroxide (NH4OH) and complexes formed. Found that ammonium hydroxide (NH4OH) 0.15% (v / v) copper is extracted from the material. Born and brought to the compound. Tai O's off the amide (DTO) 0.05% (w / v) to monitor the concentration of 0.08 ppm copper to assembly Test Kit will cost only 13 baht.