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It is indeed possible to change between these phases adiabatically. Since, as you noted, the ground state changes between being a superfluid and a Mott insulator, starting in the ground state and making an adiabatic change means that you track that change in state by definition. Note that this diagram is only formally true for the Grand Canonical ensemble, ...

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While the answer of wbeaty is very interesting in showing points relevant in practice, I think all the answers are still missing an important and simple theoretical point, which you should consider to understand the process. vapour pressure does mean two different things as used above. First, the pressure, the existing water vapour would have (if it were ...

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When the vapor pressure is equal to the external pressure, there will form a bubble. Not true. Instead, when the vapor pressure is equal to the external pressure, then any existing bubbles will begin growing continuously. And, if no bubbles are already present, then the water will superheat far above the boiling temperature, yet no bubbles will ...

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If you can't read a phase diagram, a good set of steam tables can answer your question. BTW, water can only exist as a vapor and a liquid in equilibrium when conditions place it below the saturation line. For a pressure of 15 bar (1.5 MPa) absolute, the saturation temperature is 198.3 C. At this pressure, only superheated vapor exists at temperatures ...

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If we vary conditions (temperature/pressure), such that an FCC-BCC phase transition occurred, how would we know the BCC lattice formed? In this paper Zhang & Chen used Möbius pair-potentials to model NaCl phase transitions in an MD simulation, so I am not sure how relevant it is to your question, but they use several indicators of the FCC-BCC ...

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The key is: Landau theory doesn't assume the order parameter is small. All it assumes is that the free energy is analytic in the order parameter. One then usually expands this free energy up to some order (which is possibly by definition of 'analytic'). It is key to realize that expanding a function in a variable to some order does not mean this variable has ...

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It's irreversible. The reason can be easily understood when you look the molecular properties of water The presence of a charge on each of these atoms gives each water molecule a net dipole moment. Electrical attraction between water molecules due to this dipole pulls individual molecules closer together, making it more difficult to separate the ...

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What bothers me is that if (ferro)magnetism stems from the arrangement of electrons in various orbitals (the imbalance in total electron spin), why don't a lot more materials, including basic elements, have a Curie point? What makes the very few ferromagnetic materials so unique? Not all materials display magnetism or paramagnetism. Materials may ...

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Estimation: I want the two densities of vater and vapour to become approximately equal. the density of water is nearly constant the vapour pressure (you can derive this from the above mentioned Clausius-Clapeiron-equation) is approximately exponential in $1/T$. This means, that if you increase pressure by a factor, the inverse of the evaporation ...

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