Entropy: help a brainlet out

>>8998750
It's the logarithm of number of meaningfully different arrangements that give the same physical properties.

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Things want to seperate n shit.

>>8998761
so is there like a force that drives them towards this?

>>8998750
entropy is literally thermal energy that is unable to do work

dQ/T

>>8998750
One way to think aobut it:

If you have a force applied to an object and the object moves a distance then you do work. Force and displacement are complimentary variables and when multipled you get the units of energy.

Pressure and volume are complimentary and so are entropy and temperature.

Usually one is intensive (T) and one is extensive (S).

The unit is J/K

Let the energy of a thermodynamical system be [math]E=E(T,p)[/math] i.e it is depended of pressure and temperature.


The differential is [math]dE=\frac{\partial E}{\partial T}dT+ \frac{\partial E}{\partial p}dp [/math]


What is
[math]\frac{\partial E}{\partial p}[/math]? It is volume of the system.


[math]\frac{\partial E}{\partial T}[/math] Is called entropy.

>>8998762
Not per se, but it can be determined and described with statistics

I found the card analogy useful

>>8998761
>Things want to seperate n shit.

Nigga what. Things want to mix n shit.

https://en.wikipedia.org/wiki/Entropy_of_mixing

>>8998762
Not really, it's a matter of probability. In all of the configurations that things could be in, there are a lot more ways for things to be in disorder than for things to be ordered.

>>8999076
Does that mean that entropy is more the result of the mathematical structure of reality than any sort of specific physical property? Excuse me if that sounded too vague.

>>8998750
Its liek wen u clean ur room but it get messi agan haha

>>9000188
That's generally the way I think of it, but I don't know if I'm correct

>>8998762
Motion

>>8998750
>Why are the units in J/mol*K and how does that make any logical sense?

This confused me for a while too, but it's just because of how the Boltzmann constant is defined.

You can do thermo in "natural units" where temperature is measured in Joules, and then entropy is dimensionless.

Watch this series of lectures by Leonard Susskind and he'll explain it in an intuitive way:

https://www.youtube.com/watch?v=D1RzvXDXyqA

Hope this helps!

>>8998763
rly maed me think

>>9000212
Honestly that's so fucking beautiful.

>>9000324
Why?

>>9000351
Because you can discover how the universe works without performing a single experiment thanks to mathematical truths. Boltzmann's work on thermodynamics is kind of the gold standard for physics, isn't it?

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>>9000308
literally exactly what entropy is

>>8999076
no. entropy is the amount of thermal energy that cannot be used to do work.
that is why entropy always increases.
thermal efficiency is always less than 1, meaning all processes will have some thermal energy that was unable to be converted to do usable work. This is the amount of entropy that was generated. This cannot be negative, because there are no processes with thermal efficiencies above 1

>>9000373
(I wasn't even being ironic lol)
That's a better definition that hurr disorder

>>9000355
Guess I never thought about it like that

>>8998750
J = energy, you're talking about energy so there's that.
/mol = not mass but similar because a light atom and a heavy atom act more similar in a system to each other than two light atoms and two heavy atoms. So its the amount of shit you've got going on there. If you've got lots of shit that is the same size and its just fucking laying there it is less lumpy than fewer things doing more interesting shit.
/K - It just exists so you can talk about entropy and heat so the units all work out.

In general if you have a lumpy system with energy differentials you can do work. If you've got a boring homogeneous system its just fucking stupid and sits there doing nothing.

>>9000384
What makes energy dissipate as heat and unavailable for work? Why are some processes more entropic than others? What does it mean for, let's say a peptide, to be highly entropic?

>>9000448
Not the guy you responded to but that might be in refer to degrees of freedom of the peptide structure

>>9000448
https://en.wikipedia.org/wiki/Carnot_cycle

>>9000448

In a mechanical system, friction would be responsible for a lot of entropy, right? Plus poor insulation.

>>8998762
Yeah it's usually called "time"