The Experiment

       Having developed a mathematical model with some modest rigor and roundly conjectured, it is desirable to test their veracity.  Toward these ends, an experiment was performed.  Both time and toil were expended to develop a successful and robust procedure for the Belousov-Zhabotinsky Reaction.  Fortunately, it was not all for naught.  A solution of Belousov-Zhabotinsky reagent was prepared using ferrion as an indicator (see below for the exact procedure).  In the mathematical model previously developed, it was the cerium ions (Ce4+) responsible for producing visible growth patterns of propagating waves.  In this experiment, however, ferrion was employed to heighten the visual experience of the process.  For simplicity's sake, let us assume that the ferrion reacts identically to the cerium ions.  That is, a graph of its relative concentration verses time would oscillate identically to that of cerium.

        Care was taken to insure the layer poured into the Petri dish was as thin a experimentally possible (approximately 2mm thick).  Patience was rewarded.  Concentric circles radiated across the dish and spirals unwound, colliding and forming fascinating geometric patterns, sights that even those unfortunates bereft of scientific curiosity would stop and admire.  The Belousov-Zhabotinsky Reaction, indeed, proved to be a spatio-temopal oscillator.  Therefore, our assertions seem to have merit.
     

         Through much experimentation, the the following combination of reactants yielded the most striking and dramatic growth patterns:

    10ml 0.48M malonic acid 
    10ml saturated KBrO3 
    20ml 0.6M H2SO4 
    10ml 0.005M ferrion 
    0.15 g Ce(NH4)2(NO3)6
     
    Mild heating improved the aesthetic quality of the patterns and shortened the time required for their emergence and development.  Also, adding a small amount of clear liquid soap allows for a thinner layer of reactant by reducing the surface tension. 

         To download a full movie of the Belousov-Zhabotinsky Reaction, proceed to one of the following links: 
     

    The Belousov-Zhabotinsky Reaction (avi format - 4mb) 
    The Belousov-Zhabotinsky Reaction (quicktime format - 1.9mb)