I Would an unstable emulsion separate in the abscense of gravity? How?

AI Thread Summary
In a microgravity environment, the separation of two immiscible liquids, such as water and oil, may still occur, potentially leading to a spherical layered structure. The layering could be influenced by properties like surface tension rather than gravity, which typically dictates that the lower density liquid sits atop the denser one. Smaller droplets might segregate more effectively due to cohesive forces among water molecules, while larger volumes may not interact significantly. Additionally, Brownian motion could facilitate the coalescence of small oil droplets into larger blobs over time. Overall, the dynamics of liquid separation in the absence of gravity remain complex and uncertain.
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If you have two different liquids (water and oil for example) mixed together and free floating without gravity, will they separate as they do here on Earth? If so, what property would determine the layering structure?
If you have two different liquids (water and oil for example) mixed together and free floating without gravity, will they separate as they do here on Earth? If so, what property would determine the layering structure? I suspect they would separate, and if left undisturbed probably form a spherical layered structure. But which liquid would be on the outside and which would be on the inside? In the presence of gravity, the lower density liquid would lie on top, but in the absence of gravity is it a function of surface tension? Or some other property(ies)?
 
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Who says they will separate into a layered structure? Why wouldn't the oil just form globules without globally coalescing?
 
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I'm unsure. I suppose this can't be the case for large amounts of liquid. I imagine if you had a blob of 1 m^3 of water and two little drops of oil on either side, they wouldn't have any way of even knowing about each other. For smaller drops though, I was thinking the cohesive attraction between water molecules would squeeze the oil out of its way and make it energetically favorable to segregate the two liquids completely.
 
thermodragon said:
I'm unsure. I suppose this can't be the case for large amounts of liquid. I imagine if you had a blob of 1 m^3 of water and two little drops of oil on either side, they wouldn't have any way of even knowing about each other. For smaller drops though, I was thinking the cohesive attraction between water molecules would squeeze the oil out of its way and make it energetically favorable to segregate the two liquids completely.
I'm unsure also, but it seems to me that the cohesive attraction between water molecules has already been satisfied by the occurrence of the phase separation. But maybe self-gravitation of the fluids could contribute to very very slow coalescence and segregation over very a long period of time.
 
If there are many small oil droplets with a short distance between them, they can also reach each other by Brownian motion and form larger blobs.
 
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