The dynamics of galvanostatic dissolution of nickel in sulfuric acid is investigated. The transitions (bifurcations) between regions of different behaviors are identified by a dual galvanostatic-potentiostatic mode of operation, and their loci are mapped in the plane of current vs acid concentration. These lines merge at a singular point characterized by two vanishing eigenvalues. A cusp-shaped region of birythmicity is mapped at intermediate concentrations. In the second part, observations of deterministic chaos are presented and characterized by the time trace, spectral density, phase portrait, Poincaré section and return map. The attractor is characterized by the different measures of chaos (dimensions) related to the Liapunov exponents. The roads to chaos via quasiperiodicity and via the period-doubling scenario are demonstrated. The latter transition is triggered by a potential gradient along the working electrode.
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Acknowledgements-We wish to thank Professor H. Yarnitzki for fruitful discussions, and help with equipment. This work was supported by the US-Israel Binational Science Foundation.