| Abstract: | A large rate increase of the oxidation of hydroxylamine by iodate has been shown in frozen aqueous solution as compared to the supercooled one. The experiments were conducted under frozen conditions at ?5°, ?10°, ?15°, and ?20°C and in liquid solution at 0°, ?5°, and ?10°C, as well. At given time intervals the progress of the reaction was traced by the pH decrease of the unbuffered samples. The around 500-fold enhanced reaction rate of the frozen samples (at ?5° and ?10°C) points to an important role of the ice itself beside the increased solute concentration in the compartmentalized heterogeneous system. The contribution of ice to this pH-regulated oxidation is discussed as a consequence of the high mobility and transfer rate of proton on the ice surface. © 1993 John Wiley & Sons, Inc. |
