J. Thourey

Synthèse du pentafluorotellurate IV de sodium NaTeF5 en milieu fluorure d'hydrogène anhydre. Préparation du tétrafluorure de tellure TeF4

Abstract A new synthesis of sodium pentafluorotellurate IV has been performed in liquid hydrogen fluoride. Tellurium tetrafluoride is prepared by thermal decomposition of NaTeF 5 under vacuum : NaTeF 5 → NaF + TeF 4

Synthese et caracterisation de fluorotellurates IV alcalins et d'ammonium partie I. Etude du pentafluorotellurate IV de lithium LiTeF5

Abstract Lithium pentafluorotellurate (IV) LiTeF5 has been prepared by different methods: • slow evaporation of a 1/1 mixture of lithium fluoride and tellurium dioxide or tellurium tetrachloride in anhydrous hydrogen fluoride, • heating a 1/1 mixture of lithium fluoride and tellurium tetrafluoride. LiTeF5 is orthorhombic (a = 9,52 A b = 9,12 A c = 11, 60 A)

Synthese et caracterisation du pentafluorotellurate (IV) de sodium NaTeF5

Abstract Sodium pentafluorotellurate (IV) NaTeF5 has been prepared by slow evaporation of a 1 1 mixture of sodium fluoride and tellurium dioxyde in 50 % aqueous hydrofluoric acid. NaTeF5 has an orthorhombic structure, parameters of which are a = 9.10 5 A b = 11.30 6 A c = 10.12 A

Mise au point d'un calorimetre de reaction en milieu fluorhydrique - enthalpies de dissolution de kf dans les solutions aqueuses de HF

Abstract A calorimeter designed for studies of reactions in hydrofluoric acid has been constructed. Enthalpies of dissolution of KF in aqueous solutions of HF (from 1,05 N to 28,3 N) have been measured.

Pentafluorotellurate IV de pyridinium C5H5NHTeF5: paramètres cristallins ― enthalpie de formation

Abstract Pyridinium pentafluorotellurate IV (PyHTef5) is orthorhombic (a = 12,87 ± 0,01 A; b = 5,57 ± 0,01 A, c = 13,71 ± 0,01 A).The temperature of fusion determined by D.S.C. is 114 ± 0,5°C. The standard enthalpy of formation determined by reaction calorimetry is ΔfH°298 = -1319 kJ.mol-1

Etude des enthalpies de dissolution A 298 K des fluorures alcalins dans les solutions aqueuses de HF

Abstract Enthalpies of solution of alkali fluorides in aqueous HF have been measured over a wide range of HF concentrations.

Etude de la cristallisation du trimetaphosphate de sodium vitreux. Deuxieme Partie: Aspect thermodynamique

Abstract The enthalpy of crystallization of vitreous sodium-trimetaphosphate is determined and studied versus temperature and time. Isotherm calorimetric studies were performed on glass samples annealed at 310°C and 320°c for various times (2 to 24 hours). Using both thermodynamic and crystallographic results ( Part I ), we proposed and tested a kinetic model for the crystallization of vitreous sodium-trimetaphosphate. This model is in good agreement with experiments.

Mise au point d'un appareillage de preparation et de manipulation de melanges anhydres HFNH3MF (M alcalin) — tension de vapeur totale au-dessus de solutions HFNH3 riches en HF

Abstract An apparatus for preparing and handling HFNH 3 MF mixtures (M alkali metal) has been designed and constructed. The vacuum line made of plastic materials (PVF 2 , PTFCE, PTFE) allows the purification of anhydrous hydrogen fluoride, preparation and analysis of HFNH 3 or HFNH 3 MF mixtures and their handling for further study or destruction. Total vapour pressures above HFNH 3 binary mixtures rich in HF have been measured and are described as a function of ammonia concentration and temperature (−10 to +20°C).

Systemes pyridine (methylpyridines) : HF, H2O. I, Enthalpies de dissolution de la pyridine et des methyl (2 et 3) pyridines dans les solutions aqueuses d'acide fluorhydrique

Abstract en]Enthalpies of solution of pyridine and 2 and 3 methyl-pyridines in aqueous solutions of hydrofluoric acid have been measured by reaction calorimetry for a range of acid concentration from 0, 1 to 28 molar. Enthalpies of formation of pyridinium fluorides have been calculated.

Enthalpies de dissolution du fluorure et de l'hydrogenofluorure d'ammonium dans l'eau

Abstract The standard enthalpies of dissolution of NH 4 F and NH 4 HF 2 have been measured. From these experiments the standard enthalpies of formation of solid NH 4 F and NH 4 HF 2 , have been derived. These values are δH° 298 NH 4 F = −466.63 ± 0.90 kJ.mol. −1 and δH° 298 NH 4 HF 2 ± −810.26 ± 0.90 kJ.mol. −1