Abstract
The periodate oxidation of hydroxylamine exhibits a complex and variable stoichiometry at pH 5. There are two limiting cases. In excess periodate the products are nitrate and iodate, while in a large excess of hydroxylamine I04~ is reduced to I", and the nitrogen-containing product is N20. The formation of nitrite ion and iodine is important when neither of the reactants is present in large excess. The reaction shows clock type kinetics in closed conditions if no buffer is present. In a flow reactor sustained oscillations in [H+], in color, and in redox potential are found experimentally in a narrow range of flow rate and input concentrations. A simple model is proposed to explain the oscillation.