The kinetics of dissolution of silica 'Monospher' into water as regards its dependence on time and pH was investigated at background electrolyte concentrations of 0, 0.001, 0.01 and 0.1 mol l(-1). The dissolved amount of silica depicted as a function of time and pH forms a dissolution surface. This surface can be modeled by four deprotonation equilibria and four elementary reactions. The concentration of background electrolyte increases the rate of dissolution and influences the shape of the dissolution surface.