Abstract: The present invention discloses a method for thermochemical production of hydrogen and oxygen from water by a low temperature, multi-step, closed, cyclic copper-chlorine (Cu—Cl) process involving the reactions of copper and chlorine compounds. A method for production of hydrogen via Cu—Cl thermochemical cycle consists of four thermal reactions and one electrochemical reaction and one unit operation. The cycle involves six steps: (1) hydrogen production step; (2) copper production step; (3) drying step; (4) hydrogen chloride production step; (5) decomposition step; (6) oxygen production step. The net reaction of the sequential process is the decomposition of water into hydrogen and oxygen. The methods for production of copper oxide which comprises contacting copper chloride particles with superheated steam and production of oxygen comprises reaction of copper oxide with dry chlorine as a part of hydrogen production by thermochemical Copper-Chlorine (Cu—Cl) cycle.