2825.50 - Copper oxides and hydroxides:

This HTS category, 2825.50, specifically covers copper oxides and hydroxides. These are inorganic chemical compounds where copper is bonded with oxygen or hydroxide groups. Examples include cupric oxide (CuO) and cuprous oxide (Cu₂O), as well as various forms of copper hydroxides. These substances find applications in pigments, catalysts, wood preservatives, and as intermediates in the production of other copper compounds.

Distinguishing 2825.50 from its sibling categories is straightforward. While other entries within the broader group 2825 deal with hydrazine, hydroxylamine, lithium, vanadium, nickel, germanium, and zirconium compounds, this heading is exclusively reserved for compounds of copper. For instance, 2825.40.00.00 pertains to nickel oxides and hydroxides, which are distinct from the copper-based compounds classified here.

The subcategories within 2825.50 further refine the classification based on the specific form of copper oxide or hydroxide. 2825.50.10.00 covers cupric oxide, characterized by copper in the +2 oxidation state. 2825.50.20.00 addresses cuprous oxide, where copper is in the +1 oxidation state. Lastly, 2825.50.30.00 encompasses the various copper hydroxides, such as copper(II) hydroxide (Cu(OH)₂). This granular breakdown allows for precise classification based on the chemical structure and oxidation state of the copper.