A Green-Blue-Red Belousov-Zhabotinsky Reaction

Kurt Seligmann describes a special type of oscillation in his Weltreich der Magie . 

Three 600-mL beakers, 2-L beaker or glass jar, magnetic stirrer with stirrer bar, 500-mL and 50-mL measuring cylinders, safety glasses, protective gloves. 

KBr03 or NaBr03, distilled water, malonic acid, KBr or NaBr, Ce(NH4)2(N03)e, 2.7 mol/L H2SO4 (150 mL concentrated H2SO4 diluted to give 1 L of solution), 0.5 % ferroin solution (0.23 g FeS04 7 H2O and 0.56 g 1,10-phenanthroline C12HSN2 dissolved in 100 mL of water). 

The addition of the redox indicator ferroin causes the classical oscillation system, which was first described in detail hy A. M. Zhabotinsky, to go through the various differently colored stationary states, which undergo interconversion at regular intervals. 

The solution is rendered slightly alkaline, the volume of liquid reduced and the precipitate separated off, the latter is transferred to the container used for less toxic inorganic salts, while the filtrate is washed down the drain. 

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