ABSTRACT
In other words, a volume equal to 36% of the cavity volume is available to form a bubble large enough to become detached. Assume that a bubble has to be about 100 µm in diameter to detach (see below), this would then give an estimate of the equivalent radius of the cavity needed to expel a bubble of air from water (just) before boiling as 70 µm. The larger the volume of the cavity relative to the detachment volume of the bubble, and the narrower the opening, the lower the temperature required to expel the air bubble(s). Conversely, if the volume of the cavity is less than about three times greater than the volume of the detaching bubble, then an air bubble will not be released before the system becomes superheated with respect to the solvent. This calculation does not account for the change in solubility of the dissolved gas with temperature (supersaturation of the solute), which will have the effect of decreasing the size of the cavity needed.
