LXVI.—Calcium nitrate. Part I. The two-component system: calcium nitrate–water. Part II. The three-component system: calcium nitrate–nitric acid–water at 25°

Thermodynamic Properties and Phase Equilibria in the H2O–Ca(NO3)2 System

“…The phase diagram of the H 2 O–Ca­(NO 3 ) 2 system is shown in Figures and . It does not contain the data ,, which do not agree with most of the literature, as well as the data ,,, relating to the phases that exist only in a metastable state.…”

“…Many experimental papers − are devoted to the study of solid–liquid phase equilibria in the H 2 O–Ca­(NO 3 ) 2 system. Their results are summarized in several reference books. ,,− …”

“…One feature of the water–salt H 2 O–Ca­(NO 3 ) 2 system is a noticeable tendency to form supersaturated solutions, which can eventually form gels or transform into a glassy state at low temperatures. , It is also marked by the presence of long-living metastable phases − , (for example, in the case of incomplete precipitation), which significantly complicates the determination of truly equilibrium liquidus lines. Pozin et al studied metastable equilibria in a wide range of concentrations in detail.…”

Identification d'un nouvel hydrate du nitrate de calcium Ca(NO3)2.2H2O β

“…De nombreuses 6tudes du diagramme de solubilit6 du nitrate de calcium dans l'eau mettent en 6vidence un dihydrate du nitrate de calcium (Lescoeur, 1890;Basset & Taylor, 1912;Ewing, Krey, Law & Lang, 1927;Sieverts & Petzold, 1933). Dans le cadre d'une &ude de diverses propri6t~s des hydrates du nitrate de calcium (Leclaire & Monier, 1970) nous avons isol6, en plus du dihydrate d6crit dans la litt6rature, une nouvelle forme ~t 2H20 du nitrate de calcium que nous appelons la forme ft.…”

Structure cristalline du nitrate de calcium trihydraté

“…The orthorhombic high-temperature modification of solid methanol also contains infinite hydrogen-bonded chains of alcohol molecules (Tauer & Lipscomb, 1952 La formule chimique a 6t6 v6rifi6e par le dosage volum6trique du calcium ~ I'EDTA. Les mesures goniom6triques et les clich6s de Laue nous montrent que les cristaux appartiennent h l'holobdrie du syst6me monoclinique et non au syst6me triclinique cornme le pensaient Bassett & Taylor (1912) ou au syst~me orthorhombique comme l'affirmaient Frazier, Mullins & Smith (1964).…”