The inhibition of bubble coalescence by electrolytes beyond a critical transition concentration has been assessed by the relationship between transition concentration and surface tension gradients of electrolytes (d(Delta gamma)/dc) and gas solubility. The correlation between transition concentration and [d(Delta gamma)/dc](-2) was mediocre (0.74), suggesting that the Gibbs-Marangoni effect cannot fully account for inhibition of bubble coalescence. Preliminary bubbling experiments on mixed electrolytes supported this conclusion. A much better correlation was found between the transition concentration and gas solubility (represented by the exponential decay coefficient of O-2 solubility with increasing electrolyte concentration). Hence, the inhibition of bubble coalescence may be linked with the decreased dissolved gas concentration in the electrolyte solution.