Calcium vapor pressure, high temperature

White crystal, powder or flake highly hygroscopic the compound and its solutions absorb moisture from the air at various rates depending on calcium chloride concentrations, relative humidity and vapor pressure of water in the air, temperature, surface area of exposed material, and the rate of air circulation at 40% and 95% relative humidity and 25°C, one gram anhydrous calcium chloride may absorb about 1.4 g and 17 g water, respectively. (Shearer, W. L. 1978. In Kirk-Othmer Encyclopedia of Chemical Technology, 3rd ed., vol. 4, pp. 432-6. New York Wiley Interscience) density 2.15, 2.24, 1.85, 1.83 and 1.71 g/cm for the anhydrous salt and its mono-, di-, tetra- and hexahy-drates, respectively anhydrous salts melts at 772°C, while the mono-, di-, tetra- and hexahydrates decompose at 260°, 175°, 45.5° and 30°C, respectively the anhydrous salt vaporizes at 1,935°C highly soluble in water, moderate to high solubility in alcohol. 

Calcium and particularly magnesium show excessive vapor pressure at steelmaking temperatures. Table I, but this alloyability problem has been somewhat alleviated bj - submerging the introduction of the calcium alloy under 3 meters of liquid steel (31) However, independently of vapor pressure, it is the low solubility of calcium in liquid iron which limits the effective substitution of >feiS by CaS to extremely low sulfur levels, particiilarly when the manganese content is high, 2% for example (32). 

Figure 12 shows that the measured initial rates of uptake of RbO vapor by both the clay loam and the calcium ferrite particles are close to the calculated rate over a large pressure range. In the temperature variation runs, the observed uptake rates are close to the calculated rate at high temperatures but drop to about one-half the calculated rate at lower temperatures. Below the melting point of the calcium ferrite, the amount of RbO uptake drops markedly. 

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