SECTION VI - PRODUCTS OF THE CHEMICAL OR ALLIED INDUSTRIES > CHAPTER 28 - INORGANIC CHEMICALS; ORGANIC OR INORGANIC COMPOUNDS OF PRECIOUS METALS, OF RARE-EARTH METALS, OF RADIOACTIVE ELEMENTS OR OF ISOTOPES > IV. INORGANIC BASES AND OXIDES, HYDROXIDES AND PEROXIDES OF METALS > 2825 Hydrazine and hydroxylamine and their inorganic salts; other inorganic bases; other metal oxides, hydroxides and peroxides > Copper oxides and hydroxides