Might make a good thermodynamics/chem/phys final exam Q, I wot
(then throw in stats and a tad of Chaos)
re the freeze zone, especially considering the peculiar qualities of the Hydronium molecule, how its Brownian dance might alter near-freezing
(and at each local freezing-point: YAN complex function of the local-%solute plus Its.. own molecular structure!)
Talk about umm, multidisciplinary.