J. Phys. Chem. 1981, 85, 447-450
dation would have zero propagation velocity, and states A and B would coexist indefinitely. The compositions of state A and state B corresponding to the coexistence condition, [Br-Ired = [Br-I,,, define states of equal “dynamic stability”. This equal stability applies for mixing of states by the reaction-diffusion process and is no more unique than the states of equal stability defined by mixing
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the contents of two tank reactors.
Acknowledgment. We are grateful to the donors of the Petroleum Research Fund, administered by the American Chemical Society, and the West Virginia University Senate for support of this research. The capable technical assistance of Sharon E. Pritchard is gratefully acknowledged.
I n Situ Photoacoustic Spectroscopy of Thin Oxide Layers on Metal Electrodes. Copper in Alkaline Solution Ulrlch Sander, Hans-Henning Strehblow,+ and Jurgen K. Dohrmann’ Institut fur Physikalische Chemie der Freien Universitdt Berlin, D I O O O Berlin 33. Federal Republic of Germany (Received: May 9, 1980)
A double-beam photoacoustic spectrometer is described for in situ studies of electrode processes. The electrochemical formation and reduction of oxide layers on copper (Cu20,CuO and/or CU(OH)~ of a thickness of
