# Tagged Questions

44 views

### At what temperature does air become liquid at a pressure of X bar?

... with X = 6 in my particular case. I was trying to get a phase diagram for air, only got one for nitrogen and was slightly puzzled. Here's why: I was wondering about a particular detail in ...
137 views

### Flory-Huggins ternary phase diagram with a neutral component

I am searching the literature for the Flory-Huggins phase diagram with the following components : polymer, solvent, and a third component that does not interact with the other components (just entropy ...
15 views

### Water Displacement in the Oceans As a result of Global Warming [duplicate]

Not sure if this is the right place to ask this but here goes. If the north pole ice sheets melt, everyone agrees this would be a bad thing, however one of the reasons they state for this being a bad ...
44 views

### Is there an analogue to the role of vapor in liquids and gases, but for solids and liquids?

It seems common for an ordered phase to have some amount of disorder present. For example, the average moment of a ferromagnet is less than maximum except at T=0 due to the presence of fluctuations. ...
66 views

### What will happen to water at $0^\circ$ Celsius kept in large evacuated chamber

Suppose some water is kept at $0^\circ$, in a glass (ideal container, if necessary). Now it is placed in a large evacuated chamber. What will happen? I think some water will vaporize, some will ...
186 views

### Why does ice melts, waits for 100 degrees and THEN vaporises? Why is not the process of expansion of things continuous?

What I am asking is this: Why can't a body be solid, then solid-ish, then solid-like, then liquid-like, then liquid-ish, then liquid, then vapor-like and then vapor? Why is there a rigid temperature ...
89 views

### Can there be a phase transition without change in entropy and volume?

Context: I'm studying basic thermodynamics. My lecture notes pose a question, whether there can be a phase transition without a change in entropy or volume ? Do you have any hints on where to start ...
93 views

### Dimensional Analysis : Thermodynamics

I was coming across some notes online for phase transitions. In one of the places, the author has written the Claussius-Clayperon equation in this form,  \frac{d(ln P)}{d(ln T)} = \frac{T\Delta ...
1k views

### How to freeze the Niagara waterfalls?

Here is a picture of the usual vigorous Niagara Falls (in the winter). Here is the picture of Niagara Falls frozen in 1933 (in the very cold winter). Here is the picture of Niagara Falls frozen in ...
99 views

### Do superheating and supercooling only occur from liquid?

Superheating of a liquid past its boiling point (retarded boiling) is a well-known phenomenon. However, is there such a thing as supercooling of gas past its condensation point? Conversely, ...
140 views

### Why does water ($\mathrm{H_2O}$) only have two distinct fluid phases?

Water (and other substances) can exist in many distinct solid phases (with different crystallic micro-structure), but only in two fluid phases - liquid and gaseous, in which the molecules are oriented ...
244 views

### Strange behaviour of water drops on a heated pan

I did an experiment in my home and I was surprised by the results. I heated a pan without anything in it. After some time it became very hot and I took some water (2 drops) and put it into the pan. It ...
79 views

### What is the effect of phase transition on the thermodynamic state variables of a material?

When a material undergoes a phase transition, it releases an amount of heat (under a specific temperature). So the effect of the phase transition on entropy would be equal to: \begin{align} ...
235 views

### The cooling curve of tin during solidification

I'm going to measure the freezing point of tin by recording the cooling curve. It sounds like a dull experiment because all I have to do is to heat up the tin, wait for it to cool, and the computer ...
127 views

### Is water a gas at critical density, room temperature?

I am quoting Chaikin, Lubensky, Principles of Condensed Matter Physics, p. 4. Now suppose we have a closed container of water vapor at a density of 0.322 g/cc at room temperature. As the ...
45 views

### Reversed freezing point

Helium-3's Phase diagram shows that at the right temperature and pressure combination, the solid region dips downward as temperature increases. That means that you can heat it up and it will freeze. ...
232 views

### Can Lee-Yang zeros theorem account for triple point phase transition?

Now the prominent Lee-Yang theorem (or Physical Review 87, 410, 1952) has almost become a standard ingredient of any comprehensive statistical mechanics textbook. If the volume tends to infinity, ...
416 views

### Is there a phase transition between a gas and plasma?

Does a phase transition occur as a gas is heated to create a plasma? If so, is this a first or second order phase transition? Also, does the presence of a phase transition depend on the pressure or ...
340 views

### Does this type of phase transition exist?

The short version of this question is: Is there, or could there be, a system with a phase transition where adding a small amount of heat causes a discontinuous jump in its temperature? Below are ...
416 views

### Why the free energy is called 'free'?

The free energy, $F$ of a thermodynamic system at a given temperature $T$, is defined as, e^{-\beta F} = \mathcal{Z} = \sum_{\{configuration\}} e^{-\beta E(configuration) } ...
966 views

### What is heat and how does it effect an atom?

What happens in the atom when it gets heated or cooled and turns into gas, liquid or solid? I just want to know how does heat affect an atom.
125 views

### Lattice model completely constrained by boundary data

I am dealing with a lattice model that has the peculiar property that if I specify all the spins on the boundary, by local conservation laws, the whole lattice configuration (throughout the whole ...
47 views

### Gas Circulation Using Pressure Difference

Dear all, see attached picture Please, is it possible to have the gas recirculated from the gas phase to the liquid as described in the diagram assuming the gas is not soluble in the water. These ...
55 views

### Lambda transition data points of $\require{mhchem}\ce{^4He}$

I'm looking to get some data on the lambda transition of $\require{mhchem}\ce{^4He}$. I need the data points of the specific heat vs. temperature graph, if that makes sense.
286 views

### Solidification by the application of heat

When you add heat to a liquid (or a fluid), can it be solidified? If not, why in the world does an egg's stuffs become solid (or at least no more a liquid) when you 'boil' it in water?
240 views

### Order of phase transition: Which free energy to use?

I am unclear about the adjective "first" or "second" used in phase transitions. Take the liquid-gas transition for example. If we vary the volume of the system at constant T, at some point we will ...
448 views

### Order of phase transitions

I got to read things like In case of a first order phase transition, the volume and temperature change in a discontinuous manner. However for phase transitions of higher order the change in ...
291 views

### Clausius Clapeyron equation

While reading about the Clausius Clapeyron equation from the Feynman lectures on Physics, I couldn't understand a few things from its derivation: Although the argument was pretty clear, when the ...
373 views

### Does a quantum phase transition have latent heat?

As the title says, I am thinking about the question that whether a quantum phase transition has latent heat. If so, at 0 temperature, we can drive the system by some parameter from disorder phase to ...
336 views

### How can gas from compressed air can “take” heat from surrounding environment?

I have recently been reading about why a can of compressed air gets cold when the air it contains is discharged. From what I understand the change from a liquid to a gas requires energy and therefore ...
530 views

### Lennard Jones liquid vapour phase transition

I am trying to generate a phase diagram of pressure versus temperature in a NPT ensemble using molecular dynamics method. I am using the Lennard Jones potential with 108 particles and Berendsen ...
110 views

### Parameter determining argon phase

Currently I am working a molecular simulation to determine phases of an argon NPT ensemble using Lennard Jones potential. Mainly I use the radial distribution function to determine solid, liquid, or ...
233 views

### Is the liquid/solid line infinite?

Starting from the triple point, is the melting line between solid-phase and liquid-phase infinite? If not, why does it end? Because pressures are so high that classical inter-molecular interactions ...
505 views

### First order phase transition in a classical system

I've never liked discontinuous quantities in classical physics, so I find the discontinuity in heat capacity weird. My question is, do first order phase transitions ever really exist? Or are our ...
749 views

### Salt and boiling speed

When we add a compound (salt) to a solvent, the boiling points rises. But, what could we say about the speed the solvent reaches the boiling point? It's better to add salt before or after boiling ...
3k views

### What makes water boil?

Basically how boiling takes place? Also like to know... What makes boiling point alter at various altitudes? Why bubbles rise through boiling water?
589 views

### What causes a Phase-Transition

A phase transition occurs when for example, heat is applied continuously to a liquid and after a certain time it converts into a gas. How does this process work in detail? Is their a chain reaction ...
170 views

### What kind of phases nanoparticles have (gas-solid-liquid)?

If a phase transition requires a number of particles that is in the TD-limit, can nanoparticles (~10 atoms) have phase transitions? What kind of phases and transitions nanoparticles have?
340 views

### How many particles is needed to observe a phase transition?

This is a question that was rised when we were discussing "what is melting actually". How many particles you need to form a liquid or solid. I have some remarks to point out what I want to know. Q: ...
132 views

### nature of glass transition

I am reading in some book: "The glass transition is similar in appearance to a second-order phase transition, but it is not a true thermodynamic phase transition. This is because the transition ...
297 views

### Does a negative line tension in a 3-fluid immiscible interface make sense?

This question is inspired by this question/answer pair: Is this formula for the energy of a configuration of 3 fluids physically reasonable? Consider three immiscible fluids forming contact surfaces, ...
156 views

### what is the physics just at bubble formation.

ie do a couple of molecules with more energy bang out a volume in the liquid where molecular attraction is overcome and the energetic molecules can move at random? where can I find out more about ...
113 views

### Finding two dimensional critical point

I'm reading an article about bi layered membranes which state that for the free energy function $f(\theta) = \theta \ln \theta + (1-\theta)\ln(1-\theta) + \chi \theta (1-\theta)$ Where $\phi_i$ is ...
181 views

### Does thermodynamic processess affect phase transition in solid state metals

I read an article about phase transitions and I read about thermodynamic processes such as Adiabatic process, Isochoric process, Isobaric process, Isothermal process Do these processes affect phase ...
5k views

### Best way to solve P-V-T Question

Typically in an exam or problem set we have a problem that's like this: Determine the specified property at the indicated state of water. Locate the state on a sketch of the T-v and P-v diagram. p= 3 ...
360 views

### Discontinuities and nondifferentiability in thermodynamics

In physics and engineering sources, calculus-based formalisms - whether differential forms on a manifold, or "differentials" of functions of several variables - are presented as a way of modeling and ...
What is the dominant form of heat transfer between warm water and cold air? If a $100 mg$ drop of water falls through $-40 C$ air, how quickly could it freeze? Is it credible that in very cold ...