Does pressure affect the shape of water drops according to Gibb's phase rule?

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The discussion centers on the relationship between pressure and the shape of water drops, particularly in the context of Gibbs' phase rule. It highlights that the pressure inside a spherical water drop differs from the external pressure, raising questions about which pressure is relevant for Gibbs' phase rule. Surface tension is identified as a key factor, as it causes water molecules to attract each other more strongly than they do air molecules. This attraction results in a shape that minimizes surface area, counteracting the internal pressure that would otherwise deform the drop. Overall, surface tension plays a crucial role in maintaining the spherical shape of water drops despite pressure differences.
Joe Cool
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Hello,

after I read in an exercise that the pressure inside of a spherical water drop is different than the pressure outside, I'm a little bit confused. Which is the pressure used in Gibb's phase rule and why don't the pressure change the form of the water drop?
 
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Joe Cool said:
Hello,

after I read in an exercise that the pressure inside of a spherical water drop is different than the pressure outside, I'm a little bit confused. Which is the pressure used in Gibb's phase rule and why don't the pressure change the form of the water drop?
Are you familiar with the concept of surface tension?
 
Thanks for your hint. I read about the surface tension and understand it like this: The water molecules attract each other stronger than an air molecule. So there is a force that put the volume of the water in the form that has the minimal surface. This force can balance the deforming of the drop due to the greater pressure inside the drop.
 
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