Spontaneous formation of bubbles in gas-supersaturated water.

Spontaneous nucleation of bubbles may occur in water subjected to heating, tensile stress, or gas-supersaturation. Large discrepancies exist between the threshold nucleation conditions predicted theoretically and those indicated by empirical observations. The theoretical approaches have been hampered by inadequate understanding of many of the submicroscopic and molecular properties of liquids, and experimental obstacles have included the always present and difficult to control interference from pre-existing nuclei. These problems have been most pronounced for nucleation induced by dissolved gas; indeed, nucleation thresholds for any gas/liquid system are unknown due to a lack of relevant empirical data, and no quantitative theories seem to exist.