A simple spectrophotometric determination of hydrogen peroxide solution via spectral delta from redox reaction with sodium hypochlorite.

Hydrogen peroxide (HO) is widely used in the synthesis of organic chemicals, bleaching of paper pulp, and the treatment of wastewater and as a food additive, important mediator of redox processes in natural water, and a disinfectant. However, HO stock solution is unstable and slowly decomposes when exposed to, for example, light, elevated temperatures, or metal compounds. Therefore, the ability to measure the exact concentration of HO stock solution is important for its proper use in diverse applications. This work proposes a simple method for the spectrophotometric determination of HO solution via chemical reaction with sodium hypochlorite that is inexpensive and easy to acquire. The proposed method is based on the stoichiometric spectral change of hypochlorite ion at 292.5 nm following a redox reaction with a sample solution of HO. Due to high relationship between the spectral delta value and the applied HO concentration (0.00188-0.03000%), HO stock solution can be easily quantified.