Hydrogen can be prepared by mixing steam and water gas at 673 K in presence of Fe2O3 and Cr2O3. This process is called:
Nelson's process
Serpeck's process
Bosch's process
Parke's process
CO (g)+H2O (g)673K−−−−−−−−→Fe2O3|Cr2O3(Catalyst)CO2 (g)+H2 (g)