Reactions can be characterized as combination, decomposition…

Reactions can be characterized as combination, decomposition, single-displacement, or double-displacement. Categorize the following reactions. 2H2 + O2 –> 2H2O   [red23]   2KOH + H2SO4 –>K2SO4 + 2H2O   [red25]   Fe +  2H2O  –> Fe(OH)2 + H2   [red24]   CaCO3 –> CaO  + CO2      [red26]