New answers tagged physical-chemistry
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Magnetic work and the first law of thermodynamics
"Magnetic work" generally refers to work done by a constant-current supply connected to a solenoid. Whether this work is done upon the thermodynamic system of interest depends on whether the ...
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How do you calculate the internal energy of a mixture of real gases?
For an gas mixture of constant composition, you have $$dU=C_vdT-\left(P-T\left(\frac{\partial P}{\partial T}\right)_V\right)dV$$where U is the molar internal energy and V is the molar volume. For a ...
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Estimating the energy required for dissociation from visible absorption spectra
Quiz 3 has been annoying.
From the graph, we know that the molecule dissociates at a wavelength of ~262.5 nm. We know this as this is when there are no more transitions, as indicated by the completely ...
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Why does the equation for chemical potential apply to liquids and aqueous solutes?
The kinetic theory of matter says that matter consists of individual particles be they atoms, molecules, ions, nanoparticles, even elephants; the state of aggregation can have an effect. Let's ...
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Confusion regarding order of reaction
Here is some clarification.
You are correct that order of reaction is an experimental quantity.
Just like order of reaction is is an experimental quantity, molecularity is purely theoretical quantity ...
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Are there any well documented reactions with "persistent" intermediates
The equation you give and any similar one, does not describe what happens in a reaction other that X1 moles of A react with xB of B to give this and that amount of product which may or may not be in ...
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Understanding the molar free energy to simulate phase separations (Na2O-SiO2)
As an extension of the above answer of Jon Custer, I would like to draw attention to the paper of Charles (1967). On page 634 Charles is concerned with a similar unfortunate fact that "the ...
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Variation of conductance of saturated aqueous solution with temperature
Okay, there is actually a trick way to solve the question. If any of A, C or D are false the one of the others also becomes false. (As mentioned by @AChem).
So the only option left is (B), which ...
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Why is the value of the heat capacity ratio γ the same for molecules with the same atomicity?
If we deal with an ideal gas then $C_p=C_V+R $ then $\gamma=1+R/C_V$ which then begs the question if $C_V$ is different for different molecules why is $\gamma$ constant and the same for molecules with ...
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Understanding Cahn-Hilliard Equation in terms of Units
This question is addressed here. For the units, $e$=energy (eg J), $t$=time, $l$=length.
The Cahn-Hilliard equation after the variational derivative takes the form$$\dfrac{\partial c}{\partial t}=V_{...
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Can uranium be used to color aluminium oxide based gemstones, and/or diamonds?
It's not quite alumina, but uranium(VI) oxide compounds have been used to color glass:
Oxides and uranates of uranium(VI) have been used in the past as yellow ceramic glazes as in Fiesta and to make ...
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What endothermic reactions can be effectively reversed by electrolysis?
Any elemental, i.e. single step, reaction and many more complicated reactions that can reach equilibrium, can be reversed. The forward and reverse reactions in an equilibrium situation follow the same ...
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