Activation of the C-H bond of saturated hydrocarbons (RH) by metal complexes, oxidizers, radicals in sulfuric acid and aqueous media. To establish the mechanisms of these reactions, a kinetic distribution method is used which allows studying the first limiting step. Based on the data of the kinetic, the temperature dependence of the reaction rate and substrate selectivity, compensation effects, the influence of the acidity of the environment, conclusions are drawn regarding the nature of the direct reactant (active particle) and the direction of its action. A comparison of the reactions of RH and aromatic hydrocarbons (ArH) with one of the same active particles, or in one system. Solutions of complexes of vanadium(V) in concentrated sulfuric acid in reactions with RH and ArH.