Сhromium compounds are widely used in industry, therefore, studies related to the study of the process of dissolution of oxides in various environments, including aggressive ones, are relevant. Currently, a huge amount of experimental material has been accumulated on the dissolution of metal oxides and hydroxides. Despite this, the effect of anions on the dissolution rate of these compounds has not yet been sufficiently studied, models have not been developed and generalized dissolution mechanisms have not been found. This article presents experimental studies on the effect of nitrate and sulfate ions on the dissolution rate of chromium (III) oxide and hydroxide. It was found that chromium (III) oxide and hydroxide dissolve better in sulfuric acid in the presence of nitrate ions than sulfate ions. Moreover, chromium (III) hydroxide dissolves better in acids with the addition of anions than chromium (III) oxide. Based on the data obtained, using the equation of the chain mechanism (the Barton-Stransky model), we found the functional dependence of the specific rate of dissolution on the concentration of anions in an acidic medium. With the help of the mathematical computer program MathCad, models of the dissolution of chromium oxide phases were selected. A scheme of the mechanism of the heterogeneous process of dissolution of chromium oxide and hydroxide in acidic media was proposed.