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2

Polymers such as wax definitely undergo phase transitions. You inquired about paraffin wax, which is oil-based. Paraffin wax is made of long rod-like molecules called linear straight-chain alkanes. It's solid at room temperature, but when refined as liquid paraffin and combined with water, it can act as liquid crystal, which complicates its phase diagram. ...

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Ice has a sharp melting point temperature because it is a pure substance. Wax is a mixture of higher molecular weight hydrocarbons, so it doesn't have the same sharp melting point. While I have petrochemical experience in my background, I didn't work much with waxes, so I can't give you a firm estimate of the composition, but I suspect that web searches ...

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This comes down to the fact that ice is a crystal, and wax (and chocolate) is a (glassy) polymer-like material. Here is the chart of stiffness of a polymer as it is heated. When it is cold, the polymer is in a glassy phase. As it is heated, it enters the "leathery phase", and it begins to soften. As it warms up more, the material becomes progressively ...

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The transition between the two phases is called (not unreasonably!) a phase transition, and phase transitions come in two flavours: first order and second order. First order phase transitions (generally) have a sharp transition temperature. Steam condensing to water is a first order phase transition and as you've pointed out occurs at 100ºC (at one ...

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Neutron degenerate matter can undergo a phase transition to a superfluid state. The process is thought to be analogous to Cooper-pairing, but the coupling interaction is of order 1 MeV, so can occur at temperatures below about $10^{9}$ K in neutron star interiors. The neutrons in the deep interior (which dominate the interior 100:1) can form a superfluid; ...

3

At least in the context of ultracold atomic fermions, the answer is no. The creation of a degenerate fermi gas is, unlike a BEC, not a phase transition. One major caveat: if there is an attractive force between the fermions, one can get a BCS-like phase transition to condensation of paired fermions. This is, of course, the case for electrons in metals, as ...

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The specific volume may vary, but the material still will be at triple equilibrium. In other words, specific volume is not an intensive variable that determines whether or not the material is at its triple point. Notice in the 3-D phase diagram that the triple line is at one pressure and one temperature. It is the boundary between liquid + gas and solid + ...

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Because specific volume or specific dipole moment, or specific "anything" are not really intensive parameters. What is a "true" intensive parameter for which the Gibbs rule holds, and what is only a "specific anything" intensive and there Gibbs does not hold, can be seen only in their relationship in the energy variation equation of state: \$dU=TdS-pdV+\mu ...

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