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A. ZWICKELASD HENRYT.IUBE
Two points in favor of the dehydration concept should be stated: (1) the chloro complex exhibits an unusual stability a t high acid concentrations. Such behavior is to be expected from a partial dehydration of the central atom, which can be considered as a diminished competition of water molecules in the formation of iron(II1) complexes. Conversely, formation of perchlorate complexes implies a competition between perchlorate and chloride ions in attaching themselves to the central
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atom, and it is difficult to see why k',should rise so steeply with acidity. ( 2 ) A very low solubility of iron(II1) perchlorate in 70Yc perchloric acid was observed. Xddition of water greatly enhanced the solubility. The extensive formation of complex ions of the formula FeC104++ can hardly be reconciled with this observation, while depletion of the hydration sphere of ferric ion .uc.oultl cuplaiii the reduced solubility. 110\ I