932. FINKELSHTEIN, V. S., AND RUBANIK, M. Y. [Kinetics of Ammonia Synthesis by Technical Iron Catalysts.] Jour. Phys. Chem. (U.S.S.R.), vol. 6, 1935, pp. 1051-1058; Acta physicochim, U.S.S.R., vol. 3, 1935, pp. 945-956; Chem. Abs., vol. 30, 1936, p. 728

932. FINKELSHTEIN, V. S., AND RUBANIK, M. Y. [Kinetics of Ammonia Synthesis by Technical Iron Catalysts.] Jour. Phys. Chem. (U.S.S.R.), vol. 6, 1935, pp. 1051-1058; Acta Physicochim, U.S.S.R., vol. 3, 1935, pp. 945-956; Chem. Abs., vol. 30, 1936, p. 7286.

Apparent energy of activation of NH₃ formation was 21 cal. per mol. Considering the various reaction energies required, it seems that the primary step in NH₃ synthesis is not nitride but imide formation by direct union of N and H.