Tham khảo tài liệu 'fungicides for plant and animal diseases part 15', khoa học tự nhiên, công nghệ sinh học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Copper in Horticulture 271 a black-brown crystal or amorphous powder. It is used in making fibres and ceramics and for welding fluxes. Cu2O presents one of the principal oxides of copper. The most common preparation of cuprous oxide is by oxidation of copper metal 4 Cu O2 2 Cu2O 2 Cu O2 2 CuO commercially however also by reduction of copper II solutions with sulfur dioxide the final product of which is reddish mineral cuprite. Cuprous oxide is commonly used as a pigment colouring of porcelain and glass a fungicide seed dressings and an antirust protection agent for marine paints. Available on the market are copper II oxides with a copper content of around 78 . Synonyms of cuprous oxide are yellow cuprocide red copper oxide dicopper monoxide dicopper oxide brown copper oxide copper hemioxide Copper nordox copper protoxide copper suboxide cuprite cuprocide fungimar dikupferoxid German óxido de dicobre Spanish oxyde de dicuivre French . Cupric chloride Copper II chloride is a light brown solid chemical compound with the formula CuCl2 and has the potential of slowly absorbing moisture and forming a blue-green dihydrate. The aqueous solution prepared from copper II chloride contains a range of copper II complexes depending on concentration temperature and the presence of additional chloride ions. Copper II chloride occurs as a very rare mineral in nature tolbachite and the dihydrate eriochalcite more common however are mixed oxyhydroxide-chlorides like atacamite Cu2 OH 3Cl. There are few preparations of cupric chloride known used as fungicide in agriculture as well a. chlorination of copper Cu Cl2 2 H2O CuCl2 H2O 2 b. treatment of Cu hydroxide oxide or Cu II carbonate with hydrochloric acid c. anhydrous CuCl2 prepared directly by the union of copper and chlorine and d. by crystallization of torrid dilute hydrochloric acid cooling in CaCl2-ice bath. CuCl2 is a yellowish to brown deliquescent powder soluble in water alcohol and ammonium chloride used as a mordant in
