TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The hydride/hydrate combination is: sodium borohydride/sodium sulfate decahydrate, where the ratio of moles of hydrate to moles of hydride is 3.8:1; sodium borohydride/cobalt(II) sulfate heptahydrate, where the ratio of moles of hydrate to moles of hydride is 5:1; or sodium borohydride/ferrous sulfate heptahydrate, where the ratio of moles of hydrate to moles of hydride is 14.2:3. The hydride is groups I, II, and III metal hydrides or borohydrides. The hydrate is aluminum ammonium sulfate dodecahydrate, aluminum fluoride trihydrate, aluminum potassium sulfate dodecahydrate, aluminum sulfate octadecahydrate, cobalt(II) acetate tetrahydrate, cobalt(II) bromide hexahydrate, cobalt(II) chloride hexahydrate, cobalt(II) sulfate heptahydrate, iron(II) sulfate heptahydrate, magnesium sulfate heptahydrate, nickel(II) sulfate hexahydrate, boric acid tetrahydrate, trisodium phosphate dodecahydrate, sodium sulfate decahydrate, sodium thiosulfate pentahydrate, copper(II) sulfate pentahydrate, or copper(II) nitrate hexahydrate. The hydride/hydrate combination comprises soluble ruthenium(III) chloride as the catalyst. The system further comprises at least one additional hydride, and/or at least one additional hydrate. The mole ratio of hydrate: hydride is selected such that the temperature of the system is not allowed to rise more than 1-10 degrees C above the selected phase transition temperature of the hydrate during the generation of hydrogen gas during the hydrolysis of the hydride. The hydride/hydrate combination also comprises at least one catalyst. The hydride/hydrate combination comprises soluble ruthenium(III) chloride as the catalyst. The relative amounts of reactant hydride and reactant hydrate are selected to achieve a predetermined final temperature of the system of 1-10 degrees C above the temperature of the highest selected dehydration reaction. The relative amounts of reactant hydride and reactant hydrate are selected to achieve a predetermined final temperature of the system of 10-30 degrees C above the temperature of the highest selected dehydration reaction phase transition. Preferred Method: The system temperature is kept at 32 degrees C. The method (M1) further comprises calculating the relative amounts of reactant hydride and reactant hydrate needed to achieve a predetermined final temperature of the system above the temperature of the highest selected dehydration reaction. The method (M2) further comprises adding at least one catalyst to the combined mixture of step (k).