K2CdOH4

K2CdOH4 is a chemical compound that is commonly described as potassium tetrahydroxycadmate, with the formula K2[Cd(OH)4]. In this formulation the cadmium center is in the +2 oxidation state and is coordinated by four hydroxide ligands in a tetrahedral arrangement. The two potassium ions balance the 2− charge of the tetrahydroxo cadmate anion, giving an overall neutral salt. In solution, the compound dissociates into K+ ions and the [Cd(OH)4]2− anion.

Structure and properties are typically discussed in terms of the tetrahedral [Cd(OH)4]2− anion paired with potassium cations. The solid is described as a white crystalline material, and the dissolved species in water are governed by the basic nature of the tetrahydroxo complex. The compound is controversial in routine handling due to the presence of cadmium, and solutions are strongly basic.

Preparation methods generally involve formation of the tetrahydroxo cadmate complex from cadmium hydroxide and excess potassium hydroxide to generate the [Cd(OH)4]2− anion, followed by pairing with potassium ions to crystallize the salt K2[Cd(OH)4]. Alternative routes include metathesis reactions of cadmium salts with strong bases under conditions favorable to tetrahydroxo complex formation.

Safety and storage considerations reflect the toxic nature of cadmium compounds. K2[Cd(OH)4] should be handled with appropriate protective equipment, and kept away from incompatible materials. Proper disposal in accordance with regulations for cadmium-containing substances is required.

Applications and context: K2[Cd(OH)4] is discussed primarily within inorganic and coordination chemistry as a source of tetrahydroxo cadmate species and as a potential precursor to cadmium oxide. It serves as a reference point for studies of metal hydroxide complexation and for educational discussions of salt formation and hydroxy ligands.