Tables 8.3a and 8.3b list the activity coefficients along the two liquidus curves calculated from the above equations. The activity coefficients approach unity as the mole fraction of the component approaches unity, which is expected behavior. At lower concentrations, the activity coefficients are less than unity, indicating attractive Au-Si molecular interactions in the liquid phase. This behavior contrasts with the strong repulsive Au-Si interactions in the solid phase, as indicated by the complete immiscibility of the two components.


The last column in the tables constitutes a test of whether the system obeys regular solution theory. If it did, according to Eq (7.42), the combination of variables in the last column should be a constant. However, the data show substantial variation of this group of parameters, indicating that nonideality in liquid solutions of gold and silicon cannot be described by regular solution theory.

Table 8.3a Activity coefficients of gold along the Au-rich liquidus in the Au-Si System

Table 8.3b Activity coefficients of silicon along the Si-rich liquidus in the Au-Si System

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Getting Started With Solar

Getting Started With Solar

Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.

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