The peculiar reaction dynamics of the Bray-Liebhafsky chemical oscillator is connected with the nonequilibrium periodic excitations of hydrogen peroxide embedded in a hydrogen-bonded water network. This was indicated by Raman spectroscopy that showed periodic, isothermal, and excessive excitation of the symmetric vibration of hydrogen peroxide. Since such an excessive excitation should be the result of a specific nonequilibrium energy distribution with the active participation of water, understanding this process can be of considerable importance in other systems in which water is the main constituent.