Questions tagged [physical-chemistry]
Study of macroscopic and microscopic phenomena in chemical systems in terms of physical laws and concepts [thermodynamics, statistical mechanics, kinetic theory, quantum mechanics...].
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Making permanent magnet using epoxy resin mixture
Is there any powder solution that can be mixed with epoxy resin to make permanent magnet? The goal is to place the mold in presence of magnetic field during curing the mixture. Please advise if the ...
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Electron Configuration in Ionic Crystal Lattice
I am studying about ionic crystals and get confused by how electrons should rearrange themselves to maintain stability for the unit cell. Also let me know if a major blunder underlies my basics here.
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Thermodynamics question given in Chemistry [duplicate]
Incorrect chemistry answer officialised Under isothermal condition, a gas at $300 K$ expands from $0.1L$ to $0.25L$ against a constant external pressure of $2$ bar. The work done by the gas is [Given ...
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How do partially soluble impurities reduce surface tension?
I have read that partially soluble impurities like phenol, alcohol, detergents, etc. reduce surface tension of a liquid. I cannot seem to find any logical explanation for the same. I know that ...
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Is sugar cube polycrystalline and why?
Sugar cube (see photo below) is made from white sugar granules (monocrystals) pressed together. Is it technically a polycrystalline and why? What forces act on neighboring sugar granules from the ...
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Why does the addition of potassium permanganate crystals to mercury produce light when shaken?
Put crystals of potassium permanganate in a test tube containing a small amount of liquid mercury and shake it in a dark room. The mixture will glow with a purple light. Is this just the barometric ...
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Is it possible to artificially create ice that is more dense than water? [duplicate]
I was reading this question that states ice is less dense than water because of the crystal structure being rigidly ordered and more far apart than in the liquid state. If this happens when ice ...
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Pulsed Electromagnetic Field (PEMF) and $\rm H_2O$ electrolysis
How do you compute the strength of external electromagnetic field to know whether it can induce electric field to cause electrolysis where water ($\rm H_2O$) is broken into hydrogen ($\rm H^+$) and ...
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Chemical Energy Requirements
I previously asked about a passage from Schroeder's "Thermal Physics" but the passage is just so full of oddities I feel the need ask another. Consider what Schroeder has to say in section 5....
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When I bite a hamburger, how come it doesn't change into ice cream? [closed]
Sorry for the absurd question, but this is something I have always wondered about as a kid.
I order a hamburger and pick it up. I bring it to my mouth and take a bite. Naturally, it remains a ...
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Does hypervelocity airflow prevent oxidation?
Suppose a 1m radius tungsten sphere is traveling through the atmosphere at sea level at 30 km/s. For a given pressure and surface temperature of the sphere, how rapidly would it oxidize?
Or more ...
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Explain colligative properties without invoking ideal solutions
I've been reading up on colligative properties recently and how the chemists' textbooks (e.g. Atkins' Physical Chemistry) explain it in terms of ideal solutions. An ideal solution is where the solute ...
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Solidification of Oxygen-Nitrogen mixtures
I am trying to understand the phase diagram published in by C.S. Barrett et al. in the Journal of Chemical Physics published in 1967. Figure 1 shows the phase diagram. What happens to the oxygen in ...
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How to measure the line width of an NMR signal?
I have done a basic NMR experiment, where you have a NMR oscillator, oscilloscope, DC power supply and a measuring chamber. I could not store the NMR trace in USB since the oscilloscope was quite old ...
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What if I had a chunk of pressured solid that turns to gas at atmospheric pressure?
So I let's say I have this object that's room temperature and in a pressure chamber, and it's pressured so much that it's solidified despite being made of something that would be a gas at room temp.
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