We have investigated the oxidation processes of Mg, Mg alloys with Ni, Co, Cu and powdered mixtures of these metals obtained from mechanical treatment of individual components in orbital mill, in aqueous solutions of alkali and alkaline earth metals. It was demonstrated that nearly stoichiometric amount of hydrogen in respect to Mg can be obtained at production rates of up to 640 mL/g mm by oxidation of Mg Co alloy or mechanically processed Mg Co powder ("mechanical alloy") in aqueous solutions of Na or K chlorides. Activator metals are not oxidized during this reaction. It is assumed that Mg oxidation is similar to the electrochemical corrosion process. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.