Abstract
The writer determined the heat of formation of Fe4N by means of calorimeter. Then he calculated the molecular heat of Fe2N and Fe4N by appilylng the Neumann and Kopp's law and obtained the equilibrium epuations of the eystem: Fe, Fe4N, NH3, H2 and Fe2N, Fe4N, NH3, H2 from the observed heat of formation of Fe4N by the use of the Nernst's heat theorem. These equations agree satisfactorily with the equilibrium data obtained at high temperatures. Next he prepared various iron nitrides, the composition of which was accurately determined by the X ray photogram. He studied the electrochemical properties of the iron nitrides and made clear the passive state of them. He also tested the reversible property of the iron nitridecell.
