The thermal investigation of the reaction taking place between dichromates and oxalates in the solid state has been done taking two systems of potassium dichromate-potassium oxalate and sodium dichromate-sodium oxalate. The techniques employed include thermogravimetry, differential thermal analysis, infrared spectroscopy and X-ray diffraction studies. The results indicate a stoichiometric reaction of dichromate and oxalate in 1∶1 ratio to give the corresponding chromate as the sole product.
The reaction between potassium iodate and molybdenum(VI) oxide in mixtures of different mole ratios has been investigated employing TG and DTA techniques in static air atmosphere. The products are characterised by infrared spectroscopy, chemical analysis and X-ray diffraction studies. The studies indicate the formation of mono-, di-, tri- and tetramolybdates of potassium from mixtures with 2∶1, 1∶1, 2∶3 and 1∶2 mole ratios of KlO3∶MoO3. The kinetics of the reaction was followed and the energy of activation values were computed.
Authors:I. Zay, A. Vértes, G. Nagy, M. Suba, and K. Burger
Iron injections containing high spin iron(III) complexes may undergo a reductive decomposition during preparation or storage. This process was investigated by the Mössbauer spectroscopy of ice samples prepared by quick-freezing of the injection. The comparison of three model compounds and the correlation between the osmotic pressure of the solutions and their iron(II) concentration formed in the decomposition process and determined by Mössbauer measurements revealed the reason and mechanism of the decomposition.
Authors:Cs. Vértes, I. Czakó-Nagy, M. Kolonits, E. Tálas, M. Suba, and A. Vértes
A special Mössbauer technique, MMS has been used for the study of corrosion on the surface of57Fe layers, under two types of organic coatings. The corrosion processes were followed by the Mössbauer spectra.