CCL: van't Hoff factor



Are there some simple, structural rules of thumb (a qualitative SAR, if you will) that relate the van't Hoff factor to solution concentration?  At infinite dilution, _i_ = number of particles possible from complete dissociation.  From tables I have seen, it seems though, that different ions (and ion combinations) have different slopes in a plot of i vs [solute].  Is it possible to predict that slope for an ion/ion pair?

Steve Bowlus