I. Investigation of Possible Interactions Between Thallium (I) and Thallium (III) in Solution and in the Crystalline Thallium Sesqui-Halides. II. Spectrophotometric Investigations of the Copper (II) Chloro-Complexes in Aqueous Solutions of Unit Ionic Strength. III. Optical Interaction Between the Chloro-Complexes of Copper (I) and Copper (II) in Solutions of Unit Ionic Strength. Interpretations of the Spectral Absorption of a Copper (I) - Copper (II) Dichloro-Complex. IV. Spectrophotometric Investigation of the Interaction Between Iron (II) and Iron (III) in Hydrochloric Acid Solutions

Year: 1951

DOI: 10.7907/M9F6-ZC83

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.

A radiochemical and spectrophotometric investigation of the interactions between thallium (I) and thallium (III) is used to show that the majority of the thallium (I) and thallium (III) atoms in the crystalline thallium sesquihalides do not occupy equivalent positions in the crystalline lattice and that there is no strong optical interaction between thallium (I) and thallium (III) in aqueous solutions containing perchlorate or chloride ion.

The absorption spectra of mixed solutions of copper (II) perchlorate, perchloric acid and hydrochloric acid at a constant ionic strength of 1.00 in the wavelength range 250-300 [...] are interpreted in terms of the equilibria, [...]. The equilibrium constants for these reactions are determined and the enthalpy of formation of [...] is estimated.

The non-additive light absorption in the 400-600 mp wavelength range of solutions maintained at unit ionic strength with perchloric acid and containing copper (I) and copper (II) and low concentrations of chloride ion, has been interpreted in terms of an "interaction complex", [...]. At higher chloride ion concentrations in solutions of the same ionic strength, interaction complexes of higher chloride coordination (but still containing only one copper (I) and one copper (II) in each complex) are important.

Two interpretations of the 400-600 [...] spectral absorption of [...] are advanced and discussed. At present no conclusions can be drawn as to which interpretation is to be preferred.

The light absorption in the 450-900 [...] wavelength range by mixed solutions of iron (II) and iron (III) in hydrochloric acid is interpreted as evidence for the formation of unstable but strongly absorbing interaction complexes, each interaction complex containing one atom of iron (II) and one atom of iron (III) and a number of coordinating chloride ligands. The light absorption by interaction complexes decreases with decreasing hydrochloric acid concentration and there is no interaction absorption by solutions containing [...] and no chloride ion.

Absorption spectra of iron (II) in solutions of varying hydrochloric acid concentration observed in the 700-900 [...] wavelength range are used to show the presence of iron (II) chloro-complexes.