Abstract
Complex dynamical behavior including oligooscillation (multiple extrema in concentration as a function of time) has been observed in the oxidation of thiocyanate by iodate in acidic medium. The stoichiometry of the reaction when thiocyanate
is in stoichiometric excess over iodate is I03- + SCN" + H2Q —
S042- + CN“ + + 2H+. In excess iodate the stoichiometry
+ 5ICN +
and then later the iodine is consumed. In excess thiocyanate all the iodine produced is subsequently consumed, while in
excess iodate some iodine is left at the end of the reaction. This behavior is explained via a network of nine reactions which are viable in acidic mixtures of iodate and thiocyanate.