Mendelevium Properties

Mendelevium was studies only in traced quantities. Main studies were carried out with isotope ²⁵⁶Md (C⁰_p = 28 J/molK, S⁰₂₉₈ = 75 J/molxK). In water solvent the oxidation potential of Md³⁺/Md²⁺ and Md²⁺/Md⁰ is -0.15V and -2.40V, respectively. Enthalpy of formation of infinitely diluted Md³⁺ ion in water solution is -539.68 kJ/mol.

Md³⁺ can be suspended with LaF₃ and metal hydroxides and carbonates. During ion-exchange chromatography on Dauex-50, Mendelevium dilutes before Fermium by lactic acid, citric acid or by hydroxyisobutyric acid. In contrast with other actinoids, Md³⁺ can be reduced to Md²⁺ by Zinc, sodium and zinc amalgam, ions Cr²⁺, Eu²⁺, V²⁺ and Yb²⁺. Md²⁺ can be suspended from solution by BaSO₄. In alcohol and hydrochloric acid solutions Md³⁺ can be reduced to Md⁺ by metallic magnesium. From these solutions Md⁺ can be suspended by CsCl, RbCl and Rb₂[PtCl₃].