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Why does Entropy Increase on mixing two ideal liquids

If we have $1$ mol each of two different types of ideal gasses (He or Ne for example) at the same pressure and in two equal volumes separated by a partition if you remove the partition the gasses will ...
porphyrin's user avatar
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3 votes
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Why does Entropy Increase on mixing two ideal liquids

Entropy is a measure of the number of ways (configurations) in which a system (the liquids before or after mixing) can be arranged subject to constraints such as the pressure and temperature. At the ...
Buck Thorn's user avatar
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1 vote

Why does increased reaction temperature favor endothermic but not exothermic reactions?

At equilibrium the rate of forwards and backwards reaction are equal, but the rate constants will generally not be. If the temperature is increased both of the rate constants will increase as there is ...
porphyrin's user avatar
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3 votes

Mathematical proof that more work is done in an isothermal than an adiabatic expansion?

As Poutnik states in the comments, since the integrand is the same, if we can prove that $p_\mathrm{isothermal}(V) > p_\mathrm{adiabatic}(V) \; \forall V$, that would be enough. Since pressure is ...
Metal Storm's user avatar
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3 votes

Mathematical proof that more work is done in an isothermal than an adiabatic expansion?

Let: $W_\mathrm{T}=\mathrm{isothermal\;work}$ $W_\mathrm{A}=\mathrm{adiabatic\;work}$ $y=\frac{W_\mathrm{T}}{W_\mathrm{A}}$ $x=\frac{V_\mathrm{o}}{V}$ $\lambda=\gamma-1$ Dividing both work expressions:...
Sam202's user avatar
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1 vote

Isobaric expansion vs Isobaric Free Expansion

If the volume of gas increases, but pressure stays the same, then something must be steadily supplying heat. PV = nRT yields T = PV/nR If P stays the same, and V increases, so must T. This is ...
DrMoishe Pippik's user avatar
2 votes
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Closest attempt to making a Carnot Engine

The real life inefficiency of the Carnot cycle has nothing to do with nonideality of the system elements or their frictional losses or other dissipative issues. The real life efficiency problem with ...
hyportnex's user avatar
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5 votes
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Distance between 2 layers of graphite

Carbon forms an HCP lattice and has carbons in alternate tetrahedral voids. If you remove every second carbon for a graphite layer (they are not in tetrahedral voids, though), you do get a layer of ...
Karsten's user avatar
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0 votes

Enthalpy of reaction with equal amounts of gaseous products and reactants

For an irreversible, complete reaction of the form: $$\ce{aA +bB->cC +dD}$$ The standard molar change in enthalpy is given by: $$\Delta\overline{H}^o=c\;\Delta\overline{H}_{f_C}^o\;+\;d\;\Delta\...
Sam202's user avatar
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17 votes
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Melting point of sulfur

Maurice has a plausible explanation: solid-solid phase transformations are generally sluggish or require a strong nonequilibrium condition to force them because atoms and molecules in a solid are not ...
Oscar Lanzi's user avatar
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3 votes
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Total pressure of saturated solution of air and Benzene

The vapor pressure of a volatile substance in its saturated state does not change with change in volume at constant temperature. It is like when volume decreases isothermally, some of the saturated ...
Navanieeth TS's user avatar
2 votes

Effect of temperature on voltage of a galvanic cell can't use Nernst equation?

TL;DR; version: Testing the EMF dependence on temperature does make sense, because it is not the matter just of the term $\dfrac{RT}{nF} \ln {Q}$. But you cannot use the Nernst equation directly as ...
Poutnik's user avatar
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1 vote

Radiationless energy transfer: how to arrive at the equation that give R0 between two chromophores?

This is a very late reply. The transfer rate constant is defined as $$K_{ET}=k_f\chi^2\left(\frac{R_0}{R}\right)^6$$ where $\chi$ is an orientation parameter, (assume $\chi^2=2/3$ in solution) and $...
porphyrin's user avatar
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0 votes

What happens to the waste products from crude oil refining?

In refining crude oil, almost every component is transformed into a valuable product, minimizing waste. Methane through butane gases often power refinery operations or are sold for energy. Gasoline, ...
Ryan Smith's user avatar
0 votes

Gibbs energy of an imperfect crystal

I think you have a good understanding of the matter because what you say is correct. You might find the paper by Mosquera-Lois et al. [1] interesting where they go deeper in this balancing between ...
willempie's user avatar
0 votes

Why is phosphoric acid a weak acid?

There are few reasons why $\ce{H3PO4}$ is much weaker acid than $\ce{H2SO4}$: $\ce{P}$ has much lower electronegativity than $\ce{S}$, leading to making a weaker acid. One $\ce{O}$ atom less, that ...
Poutnik's user avatar
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2 votes

When does Hartree-Fock fundamentally fail?

Anions (negatively charged atoms or molecules) are great simple examples where the HFA fails. Very often, the HFA does not even predict the anion to be stable (that the excess electron remains bound ...
Mils's user avatar
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11 votes
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Are London dispersion forces in xenon tetrafluoride strong enough to make it a solid?

The quadrupolar interaction is of some importance here. The structure below, reported by The Materials Project, shows each molecule differently oriented from its neighbors; such a difference in ...
Oscar Lanzi's user avatar
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5 votes

What happens to the waste products from crude oil refining?

The vast majority of what goes into an oil refinery is sold in some form or other. Not everything can be used straight from the fractionation column. In particular, straight run gasoline has a rather ...
Level River St's user avatar
1 vote

Will the total equilibrium pressure increase in gas phase reaction PCl5(g) ⇌ PCl3(g) + Cl2(g) after chlorine is removed?

After giving this problem more thought, I have come up with a better demonstration for why equilibrium pressure will decrease after removing the chlorine gas. Let: A = $\ce{PCl5}$ C = $\ce{PCl3}$ D = $...
Sam202's user avatar
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12 votes

What happens to the waste products from crude oil refining?

A big part of modern engineering is making sure that nothing is really a waste product - partly for simple reasons of economics (someone who can make use of more of the products will likely be more ...
Luaan's user avatar
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14 votes

What happens to the waste products from crude oil refining?

There is also petroleum coke, produced by spraying the very heaviest fractions at high temperature and pressure into a drum to try to eek out any remaining volatile components. The remaining product ...
Joel Keene's user avatar
11 votes

What happens to the waste products from crude oil refining?

Most of the excess products are reused, whether thats Bitumen(check this out https://infinitygalaxy.org/bitumen-applications-and-uses/). However there's always a small amount of waste generated during ...
Ronith's user avatar
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0 votes

Increase in equilibrium concentration of the reactant via decrease in container volume

Let the subscript (1) represent the initial equilibrium state, the subscript (0) the initial non-equilibrium state, and the subscript (2) the final equilibrium state. Assuming the values proposed by ...
Sam202's user avatar
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4 votes
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Why Is HOI a weaker acid than HOCl?

$\ce{HOCl}$ is a stronger acid then $\ce{HOI}$ for similar reasons as why $\ce{HOI}$ is a stronger acid than $\ce{HOH}$. Because the electronegativity decreases $\ce{Cl > I > H}$. For the ...
Poutnik's user avatar
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