The effect of water vapour on the behaviour of the oxygen electrode in molten nitrates

Abstract

Water vapour has been deliberately introduced into an oxygen gas electrode in an equimolar NaXO₃-KNO₃ melt at 300º. When this is done the slope of the line obtained for E_Ce11 against log[O^2-]_Total changes from the 2.303RT/2F obtained with dry oxygen to almost exactly 2.303RT/F. On discontinuing the passage of water vapour into the melt, the cell reverts to its original condition within 3 hr. These experimental results are discussed theoretically. The results also yield a value of 3.2 x 10^-2 for the equilibrium constant of the reaction O² + H₂O = 2OH-