2909.     ROTH, W. A., AND WIENERT, F.  [Thermochemistry of Iron.]  Arch. Eisenhüttenw., vol. 7, 1934, pp. 455-460; Chem. Abs., vol. 28, 1934, p. 2604.

        Heats of formation of the Fe oxides were redetermined from pure synthetic materials; methods are described in detail.  The heats of reaction, at 20.7°, were found to be:  Fe+1/2 O₂=FeO+64.6₅±0.1₂ kcal.; 3Fe+2 O₂=Fe₃O₄+266.7₆±0.2₂ kcal.; 2Fe+11/2 O₂=Fe₂O₃+195.1₉±0.2₀ kcal.; FeO+Fe₂O₃=Fe₃O₄+6.9₄±0.3₃ kcal.; Fe+11/2 Cl₂=FeCl₃+93.5₆±0.2₃ kcal.; Fe₂O₃+3Cl₂=2FeCl₃+11/2O₂+8; 07±0.4₄ kcal. A comparison with older values is added.