インジウム, タリウム, カドミウム, 亜鉛, スズ, ならびに鉛のアマルガム中での熱力学的性質

アマルガム電解精錬に関する研究 (第7報)

抄録

Thermodynamic properties of In, Tl, Cd, Zn, Sn or Pb in their amalgams were analyzed by the potentiometric measurements at high temperatures 150 to 200°C. In the cases of Zn, Pb, and Sn amalgams, their activity coefficients increased rapidly with temperature, but those of In, Tl and Cd amalgams decreased gradually. A difference between a normal amalgam potential for an amalgam and a standard electrode potential for a metal, E*, was studied. It was known that the value of E*indicated a deviation from a value calculated by Raoult's law. A temperature dependence of activity, partial molar enthalpy change, and a concentration dependence of temperature coefficient of e. m. f., partial molar entropy change, were discussed in relation to types of amalgam. It was seen that the potential difference between the metal and its saturated amalgam, Es, for In and Tl was zero while -8 to-2mV for Cd, Zn and Sn. Therefore, In and Ti amalgams were considered as a simple mixture of mercury and each of the metals. On the other hand, Zn, Cd, Sn and Pb amalgams were regarded as a complex such as Hg_xM_ywhich was dissolved in a mercury or a simple mixture of mercury and each of the metals.