CdH2O62

CdH2O62 denotes the hexaaquacadmium(II) ion, [Cd(H2O)6]2+. It represents the aquated form of cadmium(II) in aqueous solution, where the Cd2+ center is coordinated by six water molecules.

Structure and properties: The hexaaquacadmium(II) ion features an octahedral coordination geometry with six Cd–O interactions. In solution, the complex is typically colorless, reflecting the d10 electronic configuration of Cd2+. The primary form of cadmium(II) hydration in water is this [Cd(H2O)6]2+ species, though it can engage in further hydration or association with counterions depending on the chemical environment.

Occurrence and behavior: In neutral to slightly acidic aqueous solutions, cadmium(II) ions are largely present as the hexaaqua complex. With increasing pH, hydrolysis occurs, leading to species such as [Cd(H2O)5(OH)]+ and, at still higher pH, precipitation as Cd(OH)2(s). The hexaaquacadmium(II) ion thus serves as a fundamental model for studying hydration and hydrolysis of Cd2+ in aqueous chemistry.

Applications and relevance: The [Cd(H2O)6]2+ ion is a common reference species in coordination chemistry and environmental chemistry, illustrating how divalent metal ions interact with water ligands. It provides insight into cadmium behavior in natural waters and in laboratory studies of metal–water interactions and hydrolysis.

Safety: Cadmium compounds are toxic and environmental and health risks are significant. Handling requires appropriate safety precautions, including avoidance of inhalation or ingestion and proper waste management.