Competing Reactions with Initially Separated Components

The first theoretical and experimental study of a competitive reaction with initially separated components is presented. Rich spatiotemporal reaction front patterns are produced by a simple theoretical reaction-diffusion model. Such patterns are observed experimentally for the reaction ${\mathrm{Cr}}^{3+}+\mathrm{xylenol}\mathrm{orange}\left(\mathrm{XO}\right)\to \mathrm{products}$. The conditions for these front patterns are significant differences in the microscopic reaction constants and in the initial densities of the competing species.