The following diagram represents the liquidus surface (polythermal projection) in the ternary phase diagram for BaCl2-NaCl-KCl-CaCl2 (the composition units are wt%). Assume that there is no solid solubility of the compounds in one another.
Sketch a blank ternary diagram and draw the isothermal section at 750°C. On the diagram, trace the path of the liquid composition when material consisting of 60 wt% BaCl2, 20 wt% NaCl, and 20 wt% KCl-CaCl2 is cooled from 90°C to 500°C. Assume that equilibrium is maintained at all temperatures. From part b above: what will be the weight fraction of liquid when the liquid just reaches the ternary eutectic temperature (500°C) but has not solidified as a primary eutectic? That is, what will be the fraction of fine primary eutectic in the material when it is all solidified? What will be the weight fractions of the coarse BaCl2 and NaCl crystals in the completely solidified material?