Complex motion of precipitation bands
نویسندگان
چکیده
Formation and dynamics of an Al(OH)3 precipitation ring is studied by diffusing NaOH into a gel containing AlCl3. Limited feeding of the outer electrolyte (NaOH) is found to yield an intricate ring-dynamics which involves stopping and reversal of the direction of motion of the precipitation ring, and evolution into stationary multi-ring structures. A model of the ring-dynamics is developed by combining a phase separation scenario for the precipitation with the redissolution (complex formation) of the precipitate in the excess of the outer electrolyte.
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