Transition scenarios during the evolution of the Belousov-Zhabotinsky reaction in an unstirred batch reactor

We report experimental evidence of transition scenarios during the chemical evolution in an unstirred closed Belousov-Zhabotinsky (BZ) system. We demo nstrate that during its chemical evolution the system spontaneously gives t he following sequence of dynamic behavior before reaching equilibrium: peri od-1 --> quasiperiodicity --> chaos --> quasiperiodicity --> period-1. Two transition scenarios are observed: at the onset of chaos and at its end. On e appears as the minor image of the other. Our observations support the vie w that closed chemical systems also are able to show chaotic behavior and t he corresponding transition scenarios.