EQUILIBRIUM POTENTIALS OF GOLD IN MOLTEN NACL-KCL-CSCL EUTECTIC

Equilibrium potentials of gold are measured at 500 - 700 degrees C in a molten ternary NaCl-KCl-CsCl eutectic containing 0.04 - 2.0 mol % of gold. The temperature dependence of equilibrium potentials is linear, and the equilibrium potential shifts in the negative direction as the temperature increases. The average valence of gold ions in equilibriu m with the metal determined from the slope of the equilibrium potentia l isotherms is 0.92 +/- 0.06. The change in the Gibbs energy at the fo rmation of gold monochloride from the elements in the melt is calculat ed. The conclusion is reached that gold monochloride interacts with th e NaCl-KCl-CsCl melt. The reasons for the appearance of positive slope s of the equilibrium potential polytherms are analyzed.