1788. KLEPPA, O. J. [Equilibrium CoO+H=Co+H2O. The Molar Entropy of Cobaltic Oxide.] Svensk Kem. Tid., vol. 55, 1943, pp. 18-25; Chem. Zentralb., 1943, I, p. 1970; Chem. Abs., vol. 38, 1944, p. 4855.

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Literature Abstracts

1788. KLEPPA, O. J. [Equilibrium CoO+H=Co+H₂O. The Molar Entropy of Cobaltic Oxide.] Svensk Kem. Tid., vol. 55, 1943, pp. 18-25; Chem. Zentralb., 1943, I, p. 1970; Chem. Abs., vol. 38, 1944, p. 4855.

Equilibrium was studied by the stream method, and values were obtained that agree with the static method. For the constant K_p=pH₂O/pH₂ the heterogeneous equilibrium gives K_p_°³⁹⁸=39.35, K_p⁸⁴⁹=44.2, K_p⁷⁹³=51.3, K_p⁷³⁸=56.8 (temperature in degrees Kelvin). According to ∆F=-RT log K_p, the change in free enthalpy (reaction-work) can be calculated, and also the heat content by means of van’t Hoff’s equation, which then can be determined at other temperatures with the help of molecular heat. The normal values ∆F²⁹⁸=-3461 cal. per mol., and W_p²⁹⁸=859 cal. per mol., are obtained, from which it follows that ∆S²⁹⁸=8.73 cal. per mol. per degree. From the known normal entropies of H₂O, Co, and H₂ it follows that S²⁹⁸ Co=11.94±0.2 cal. per deg. mol.