Outgassing is the phenomena of spontaneous and continuous evolution of gas molecules from a surface (usually solid) (like the wall of a vacuum chamber) when it is exposed to vacuum. My question is that if the vacuum is replaced by a liquid, does outgassing occur into the liquid from the solid?
Yes, there are other examples of metals outgassing such as steel that is charged with hydrogen either by corrosion or welding. I have seen hydrogen charged steel slowly releasing hydrogen into water. A friend even replaced the water with a clear epoxy cast over a fresh weld. The epoxy captured the hydrogen released before the epoxy had a chance to set.
Yes, but you would not call it outgassing, evidently.
If the volatile species is adsorbed on a surface, the process of its removal should be called desorption, not outgassing. The latter term seems more appropriate for dissolved species. But for porous media, the distinction may be difficult.
The molecules of the volatile species have no awareness of the phase which receives them; they simply move to the location where they have the lowest chemical potential. Therefore hydrogen molecules would naturally move from steel to water, as Stephen observed, as long as the H2 solubility in water is not exceeded.
During both welding and cathodic charging of hydrogen in metals, atomic hydrogen (one H not H2) is "dissolved" in the steel. As long as it does not find a site inside the solid to combine to form H2, it remains mobile and can diffuse out of the steel. It is the atomic hydrogen that is released from the metal, where it rapidly combines to form H2. Hence, this is not an adsorption/desorption phenomena, but is truly one of outgassing.
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