#free enthalpy

[silly-hermit]

The dark magic of Thermodynamic functions

Abstract: You probably won't refer to "free enthalpy" as the "Gibbs Energy" anymore (and finally there will be sense for what an 'enthalpy' even is.)

If you stumbled upon this post by using the #thermodynamic tag on tumblr, well, please lord have mercy on you. Tho, if you truly did, he most likely had forsaken you long ago.

Internal energy 'U' and enthalpy 'H', as well as their more refined (or literally, "freer,") counterparts free energy 'F' and free enthalpy 'G', all share the same unit: energy (Joules).

Sharing the same unit implies some similitude, even between two very distinct stuff: the Eiffel tower's height is not the same as mine, but we can see how they *can* be compared.

Yet, when it gets more abstract, such as energy, the nuances aren't so clear. We're not even sure sometimes that what we define actually means anything: for what we know, it could just be a convenient way to handle the values.

What I'll tell next are analogies, not images. In analogies you can manipulate two object as being truly equivalent. Because the same rules apply for both, it's great if thinking with one of them makes it easier than with the other.

Enthalpy 'H', is to internal energy 'U', what some person's overall wealth are to their bank account.

Both 'total wealth' and 'bank account' are expressed in some currency, be it €, $, or whatever. But if we want to tell how wealthy someone is, the amount of cash on their bank account isn't enough. It could currently be at 1.000€, yet the guy in question is a CEO owning a mansion, a boat, etc. So, to get the whole wealth, we add the Value of all the Possessions (for now let's call it PV) to the bank account. If we take back our thermodynamic functions, this become:

H = U + PV

Honestly I just made the PV naming pun because I could. For coherence, I rather think it's both simpler and better to call V the "Volume (of possessions)" and P the average "Price (of possessions)." Volume analogy is straightforward. For Pressure-Price, if Price is cost per volume, then its units are €/m3, which in our analogy € act as Joules, so it also adds up.

So, an enthalpy, is a total wealth. It not only includes the core bank account (U), but also all the person's (or 'system's') belongings, via PV.

This also explain why, in chemical reactions, it's easier to talk in terms of enthalpy, and internal energy is seldom used. The same as you guess someone's wealth by looking at everything they owns rather than just their bank account (which probably you can't access anyway).

Let's get back to the thermodynamic story.

Having 1.000€ of wealth (not just bank account) mean I can afford stuff up to 1.000€ (taxes included). But if I'm being rather cautious, I would think a lot before spending my whole 1.000€, or even way less, on something. There is some kind of threshold, under which I will spontaneously spend the money, but above which I'd think twice before doing so. Out of all my wealth, I subtract some of it for savings, and the rest of the wealth is free for me to use. That's what free enthalpy (or free energy) is about.

G = H - TS

I set aside some of my wealth (-TS) to stay in a comfortable state of mind. My comfortable state of mind is an analogy for my thermodynamic equilibrium state.

Thus, if we look from the thermodynamic side of the analogy, the TS term means some kind of stored away energy. Which actually is exactly that. The TS term represents the energy the system get from how 'probable' it is. This energy cannot be retrieved in any way. So to correct a bit our analogy, rather than being about "savings", it's more like "comfort investment." You already spent this money to make your life easier, and you won't get it back. So I hope it was worth your money.

Same can go for free energy and bank account, if you only think about bank account-related purpose. (Which is why most "first principles" derivations, will use the free energy in formulas rather than the free enthalpy. They care more about the energy of the particle of the system rather than the energy of the whole system, which include the work it did at some point to occupy its volume.)

We got a grasp of what TS is, but are there analogies for T and S alone? When refining any analogy, before adding new axioms, it's better if we can let the analogy produce them itself.

TS is a product, representing some 'comfort value.' It is important to not say just 'comfort' but also precise 'value', as its units are Joules, i.e. currency € in the analogy. Very often in physics or whatever, when you have a product, you can always make the individual factors analogies of "level of something" and "the value of a level of that something." So, since TS is a comfort value, it means that either T or S is "comfort level" and the other is "the comfort value of a level." Looking at their -physical- units, K and J/K, we can infer that T is comfort level while S is comfort value of a level.

It implies that 'Kelvin' are our equivalent of 'comfort level.' Which I can kinda see how: the less comfortable it is, the more restricted we feel. And at absolute 0, total restriction, we can't move at all.

For entropy, by physical intuition we may be aware that entropy quantifies how statistically favourable a system is. Fortunately I think it's quite accurate to say that "how statistically favourable" is analogous to "how comfortable" a system is.

I like that about analogies, when you're checking the logic is self-consistent, you unveil insights simplifying the whole.

To recap:

U = Bank account

H = U + PV = Bank acc. + Possessions*price of possessions = Total wealth

G = H - TS = Total wealth - comfort level* value of comfort level = Free wealth to spend

I hope this will help you in your thermodynamic journey, but be aware that whatever path you take, they all end up in hell (Boltzmann wanted to get there faster, I guess)

[solqrays]

born-haber cycle, hess' law and lattice enthapy the biggest opp

[sciencesolutions]

[tenth-sentence]

Furthermore, we have shown that the sign of ∆G depends on the signs of both ∆H and ∆S and that, when ∆G = 0, there is no driving force for chemical or physical change and the system is at equilibrium.

"Chemistry" 2e - Blackman, A., Bottle, S., Schmid, S., Mocerino, M., Wille, U.

[brandwhorestarscream]

Vector Prime, the cybertronian God of Time, was imprisoned by his siblings to prevent his meddling with the time stream, yes?

I just had a thought, about Vector Prime's prison. In theory, if anything could ever reach absolute zero, time would stop, because there would be no energy, no enthalpy, no thermodynamics, nothing. Absolute zero would be the absence of all energy, and I think that is whhat the Primes needed to trap Vector. Amalgamous the engineer and Solus the blacksmith put their heads together to create the universe's first-ever point of Absolute Zero. Vector Prime trusts them completely, and doesn't typically look into his siblings' futures as per their own request. He genuinely has no idea he's walking into a trap.

It happens instantaneously, so fast even Vector's reflexes can't combat it. He's frozen solid, and they trap him inside of his Fractal to allow time to flow unaided and undisturbed. Vector is in a cryostasis coma for billions of years, and when he does finally get out, the cold has changed him. Absolute zero causes time itself to stop, and cold causes time to slow, and all his eons of being trapped in a hypothermic nightmare have left him hardened and warped. He's so cold that he's always surrounded in a cloud of steam, causing the air around him to always look foggy. Frost spreads everywhere he touches, and time itself becomes syrupy in his immediate vicinity. Icicles grow off of him like jagged thorns, and he never seems to stop shivering. And when he finally breaks free... his siblings barely recognize him.

[materialsscienceandengineering]

Maxwell Relations

In the field of thermodynamics, equations derived from the definitions of thermodynamic potentials, and derivable from the symmetry of second derivatives, are known as Maxwell potentials. The four most common Maxwell relations relate the second derivatives of internal energy, enthalpy, Helmholtz free energy, and Gibbs free energy, to the derivatives involving temperature, pressure, volume, and entropy. The Maxwell relations allow scientists to substitute equivalent partial derivatives when one is more convenient than another (if, for example, one knows temperature and volume but not pressure, etc.).

Sources/Further Reading: (Image source - Wikipedia) (LibreTexts) (Blog post) (UC Irvine)

[monster-rinds]

Chapter 14: Not the key

We monsters are not lifeforms. Despite how well we can sometimes mimic life, we do not operate via the same mechanisms and drives.

I don’t remember if I’ve said this already, but as far as I know we don’t reproduce. We’re very singular beings, not made up of anything remotely like cells. We don’t have mitochondria, we have standing waves and strange attractors and things like that. We don’t have anything like DNA, and we’re essentially immortal. Except when we’re destroyed. So relationships built on sex are just not something that happens for us.

We just exist, and if we exist long enough and eat well enough, we can get pretty complicated. But when we adapt, it’s deliberate. It’s through learning. It’s through looking at the world around us and deciding what to do about it.

However, we do have one basic drive that we share with life, and that’s to eat. Like life, we are whorls of enthalpy and entropy that must continue to feed to function and exist.

And I’ve been doing that for a long, long time.

Even though I couldn’t sense the emanations of other monsters quite in the same way that Felicity could, because I was saving my energy for other things, I was still aware of our target since before Felicity had signaled me.

It was due to their behavior more than anything else.

It didn’t hurt that I was supercharged from being surrounded by a larger crowd of excited people than I’ve experienced in a long, long time. My ability to be alert and to think quickly was at what felt like my maximum.

It was exhilarating.

Anyway, before diving into the employee-only hallways and rooms of the convention center, Felicity seemed to decide that tending to her vessel’s needs was an essential part of her act. So, we went to where the food was, and she bought a bottle of water and an under-cooked slice of microwaved pizza. The corn dog vendor had already packed up.

And then we sat on a bench while she ate and drank, and I noticed our pursuer walk right on by without looking our direction, and then disappear into the crowd. No doubt they were planning on doubling back and reestablishing their bead on us from further away and in a less obvious position. 

To make that easier for them, I pulled out my phone and played with it for a while.

When Felicity was ready to move on to the next part of our plan, she squeezed my hand again.

I responded by beaming a smile and leaning in to kiss her on the neck.

She squirmed and giggled, and that made me feel like she maybe did have enough energy to do this.

The food and water was helping her host’s vessel, and that meant she had more reserves for herself, I thought.

I realized I’d been doing a lot of hoping lately, and that was a bad sign. A signal I was putting myself in too much danger. But I kept at it for the time being.

Still, I had a nasty trick up my sleeve, just in case. Well, an old and timeworn trick that I never-the-less was phenomenally good at.

---

Something that surprised and worried Felicity was that she was not seeing more emanants amongst the crowd of con-goers.

Obviously, there would be quite a number of riders and parasites amongst the humans, and just like herself, they were hard to detect unless they showed themselves. Even for her. But she expected to see more emanants like Synthia and more predators, too.

When Fuzzy-feet walked by and kept going, she expected it would be because another predator was nearby and had made a stronger claim on Synthia. But, if there was, she couldn’t spot it. And, after a bit, Fuzzy-feet appeared again, further back in the crowd, around the corner of the T-section in the hallway. She saw its aura wafting up above the masks and heads of the crowd around it.

That’s when she squeezed Synthia’s hand, while wondering what was keeping this convention so quiet and free of emanant activity.

Come to think of it, the theater had felt this way, too. Only a couple of emanants besides herself and Synthia had felt bold enough to make their presences known.

And then Synthia was leaning over and kissing her in the neck.

It was just an act, but it tickled and tingled, and playing up the natural human reaction of pleasure and embarrassment to it was easy. It came naturally, like the body knew what to do.

She giggled and squirmed, and then stood up, pulling on Synthia’s hand, whispering loudly, “Alright, let’s go fucking snog.”

Synthia squinted at her as she stood up after, saying, “Snog? What are you, 2004 LiveJournal?”

“I beg your pardon. It’s perfectly cromulent Queen’s English,” she retorted.

“What are you gonna do about it? Colonize me?” Synthia snapped, snickering.

“Maybe behind that door over there,” Felicity responded conspiratorially, pointing at a likely candidate for where they wanted to go. It was unmarked. It might just be a supply closet, but it looked heavier duty than that, like a light fire door.

The banter they’d fallen into was maybe a bit too old for their appearances, but this was an especially geeky place, and they were trying to be silly and weird to match their cover. No one seemed to even notice.

Their mark was likely too far away to hear them over the crowd anyway. It was mostly their body language that mattered here.

So, Felicity let Synthia look at the door, nod, grin, and then lead her to it. And then she stumbled along like before, but with a little more anticipatory energy.

Or so she hoped. She was still feeling fairly discombobulated from hunger and weakness, even if she had a little more lucidity than before.

Synthia paused before the door, saying, “Wait a second. I need to look something up. Maybe there’s a floor plan.” Then she pulled out her phone and keyed up the page for the con, and poked at a couple of links.

The map that she found didn’t include this door, but she left that up anyway and kept her phone out. What was more important was that she was more traceable this way.

“Yeah, let’s see where this goes,” she said. Then she reached for the nob and surreptitiously did something with the lock that neither Felicity nor Amber could do. Being a physical emanant with tight control over your form had its perks.

And what was behind the door was exactly what they were looking for, a service corridor, so they ducked in and closed it.

The color of the carpet changed from the pattern of the main floors to a solid dusty rose, and the walls were a simple textured eggshell. The ceiling had the worst fluorescent lighting installed.

It went back into the building several paces before intersecting with a main corridor that was twice as wide but with the same lack of decor.

Synthia led them to the first corner and around it, then paused, looking down at her phone but doing nothing in particular.

“Listening for our mark?” Felicity whispered as quietly as possible.

Synthia didn’t respond.

But after a couple of breaths she started moving again, looking satisfied.

“What was that about?” Felicity asked.

“You didn’t notice?” Synthia asked back.

“Notice what?”

“Perfect,” her partner in crime said. “I’ll explain later. Right now we gotta keep quiet and keep moving.”

Felicity shut up and looked back.

These corridors weren’t infinite, nor massive. There were solid double doors at either end of this big corridor. It looked like the halls existed in small sections between main areas of the convention center. But there were enough side corridors that they were able to do a little snake action.

At the next corner they took, Synthia paused again, squeezing Felicity’s hand for some reason.

They weren’t putting on their act anymore, or didn’t need to, but they were still holding hands, and Synthia was probably just subconsciously keeping it up. Maybe trying to be reassuring like a human.

Then they moved to the door at the end of that side hallway and paused yet again for a couple silent breaths, before Synthia opened it.

On the other side was an empty ballroom or meeting room of some sort. Maybe a party room. It was a little bigger than your typical classroom, but instead of a desk it had a dry bar in the corner to their right, and rails for lighting, with a wooden floor.

And it was completely devoid of any other furniture or fixtures or decor. Like it was being left a blank slate for whomever might book it in the future.

“Yes!” Synthia hissed. “Love it. Let’s set up behind the bar. They’ll have to go around to get at us.”

“Sounds good,” Felicity heard herself say, still looking around at the room. She really wasn’t as present as she wanted to be. She hoped that whatever Synthia was doing would give them a good edge.

She felt herself being dragged by the wrist into the room and toward the far wall where the entrance to the bar was. It didn’t make a lot of sense, she thought, because anyone bringing supplies from the service halls would have to make this same trek to get to the bar. But, sometimes things got rearranged for other reasons and thoughtful architecture got nullified.

And she had a fleeting thought that the bar and service door were like some sort of allegory for what was going on in her broader existence, but she couldn’t really explain how at the moment.

Then, suddenly, she felt herself falling.

“The mark is right on our tail, but moving cautiously,” she heard Synthia saying.

And then she lost consciousness.

---

I found myself looking back into the startled and confused eyes of someone I assumed was Amber.

Well, shit.

I lowered my head and loosened my hold on her hand after a quick squeeze, in case she wanted to let go. I could feel her bewilderment and alarm as it fed me.

“What…?” she asked, glancing around. “How…?” She at least appeared to recognize me when looking my way.

I tilted my head and gestured slowly downward with my left palm, “Hold on a moment, Amber. Let me catch my own bearings really quick.” But I waited to see her nod before doing my thing.

Then I did what I’d been doing in the hallways and put a little two-dimensional pseudodomain down covering the floor behind the bar.

We were in Portland, let’s call them pseudomains.

This is a thing I normally did when being pursued, if I had enough time and wherewithal to pull it off. And I wished I’d had the forethought to use it in the theater. But what we’d been doing there was so far outside my typical modus operandi it hadn’t occurred to me at the time. Here, however, the slow chase had prompted me to remember the trick.

“OK,” I said to Amber when I was done. “Let’s stand here in the middle of this space and wait. This might end up being a little scary, but you’re OK. You’ll be safe.”

“What are we doing? Why am I here with you?” she pulled herself together enough to ask.

“Have you had any blackouts before?” I asked her back.

She shook her head, “N… no? I don’t… Never.”

“What’s the last thing you remember?” I asked, keeping my words quick, to imply that she should answer quickly, too.

I could feel the other teratovore stepping on my second to last pseudomain. One more and they’d be walking in the door. There was no time to break the ice for Amber. She was just going to have to witness this if Felicity didn’t take back over real quick.

She scrunched up her face, and said, “I remember talking to you at the checkout counter with my friend Josephine. We were going to have fajitas.”

“You’ll probably remember more than that as you talk about it, or when you see Josephine next,”  I told her in a reassuring tone. “But that was yesterday.”

“Yesterday?” she gasped, radiating quite a bit of incredulity and fear. Good. I wanted her engaged but with lots of adrenaline and alertness.

“Yeah, and Josephine, I think, has a big huge crush on you,” I told her, based on my memories of Josephine’s emotions. “It’s probably reciprocal.”

“What?” she blinked, taken aback.

The last pseudomain registered a monstrous footprint. I had time for one last line and emotional reaction from her to recharge me before the door opened. I decided to see if I could trigger Felicity to come back forward again.

“Remember that monster that almost ate you?” I asked.

“What?!”

My plan was that, if Felicity wasn’t present and couldn’t attack our mark, I would expand the pseudomain beneath me to envelope the teratovore and trap them. To have the strongest control over it, I needed to be in the same domain as my attacker, so I didn’t want to do that with the one that was at the door.

What happened instead was phenomenally bad timing, to say the absolute least.

---

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[sarallokesh37]

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[vvtcoaching]

Thermodynamics NEET 2025 – Laws, Formulas & Tips | VVT Coaching Guide! Master Thermodynamics for NEET 2025 with important concepts, laws, formulas & preparation tips. Free notes and guidance by VVT Coaching.

[edgythoughts]

How does entropy relate to spontaneous reactions?

How Does Entropy Relate to Spontaneous Reactions?

As you're here, that probably means you already peeked at the textbook explanation and went, “Yeah no thanks.” So instead of all that science-speak, let’s go full casual mode and really get what’s going on with entropy and those “spontaneous reactions.” — First: What Even Is Entropy? Okay, imagine you clean your room. Everything’s in place. Tidy. Beautiful. Now give it a few days… and somehow your socks are in your bag, your notes are under your bed, and there’s a snack wrapper on your pillow. What happened? That, my friend, is entropy. In science terms, entropy is just a fancy way of measuring disorder. The higher the entropy, the more chaotic or messy something is. Nature has a habit — it loves to go from neat to messy. From organized to scattered. That’s why your room never magically cleans itself. —

So What Are Spontaneous Reactions? Spontaneous reactions are chemical reactions that just happen — no extra push needed. Like iron rusting. Or ice melting on a warm day. Or your banana turning brown when you forget it on the table for too long. They don’t need your help. They’re just gonna do their thing when conditions are right. But here’s the twist: “spontaneous” doesn’t always mean “fast.” Rusting takes time, but it’s still spontaneous. So don’t think of it like a sudden kaboom — think of it like a chill, inevitable process. — So How Does Entropy Tie Into This? Alright — picture this: When a chemical reaction happens, the particles (atoms and molecules) can get more spread out, more disordered, or more randomized. If that happens, the entropy of the system goes up. And guess what? Reactions that increase entropy (aka create more disorder) are more likely to be spontaneous. Let’s break it down with a few examples: ✅ Ice melting: Solid water (ice) has super organized molecules. But when it melts into liquid, those molecules move more freely = more disorder = entropy increases = spontaneous. ✅ Firecracker exploding: Before — one tiny, compact thing. After — boom, gas and heat everywhere = way more entropy = spontaneous reaction. But hold on — it’s not just about entropy. There’s a partner in this called enthalpy (which is about energy). Together, they help decide if a reaction happens on its own. And scientists put these two things together in something called the Gibbs Free Energy equation: ΔG = ΔH - TΔS Don’t worry — you don’t have to memorize it. Just know this: - If ΔG is negative → spontaneous reaction - ΔS is entropy (disorder) - ΔH is energy (heat released or absorbed) So more entropy (higher ΔS) = more likely ΔG is negative = boom, spontaneous! — Why It Matters in 2025 Understanding entropy helps us design better batteries, predict how pollution spreads, develop efficient chemical processes, and even explain why your cold coffee gets warm sitting out (and never the other way around — sorry!). In short, entropy tells us what’s gonna happen when we’re not looking. — TL;DR — Simple Version: - Entropy = disorder or randomness. - Nature likes things to be messy (aka high entropy). - Spontaneous reactions are more likely when they increase entropy. - Think melting ice, rusting metal, or mixing cream in coffee. - It’s not just about being messy — energy and temperature also play a role. — 📌 Disclaimer: This easy version is meant to help you understand the concept better. If your exam or teacher expects a textbook explanation and you write this one instead, we’re not responsible if it affects your marks. Use this for understanding, not copy-pasting. — 🔗 Related Articles from EdgyThoughts.com: What If Atoms Could Remember Past Lives 2025 https://edgythoughts.com/what-if-atoms-could-remember-past-lives-2025 How Quantum Particles Decide Their Path 2025 https://edgythoughts.com/how-quantum-particles-decide-their-path-2025 🌐 External Resource: Want the deep science behind it? Check out the Wikipedia page: https://en.wikipedia.org/wiki/Entropy — Read the full article

[anewdawnwithoutfear]

Someone asked if there's any math I enjoy, and I said stoichiometry is fine, but I just remembered that I do like calculations involving Gibb's Free Energy for some reason. ∆G°=∆H°-T∆S° would be the equation, it means the change in Gibb's Free Energy (∆G) is equivalent to the change in enthalpy (∆H) less the product of the temperature in Kelvin (T) and the change in entropy of the system (∆S), the ° here just means at standard pressure. I like it. Entropy is ordinarily a pain to deal with, because while the entropy of a system is easy, the entropy of the surrounding universe is less easy.

[i-should-have-studied]

Chemistry Sem 4 End - Mod 3

Kirchhoff's law

--- Gibbs and Maxwell Relation

--- Joule Thomson effect

--- Gibbs free energy + Helmholtz free energy

These are two equations derived by Gibbs and Helmholtz called Gibbs Helmholtz equations.

One of the equations can be expressed in terms of changes in free energy (ΔG) and enthalpy (ΔH)

This equation is called Gibb’s Helmholtz equation in terms of free energy and enthalpy change at constant pressure.

It is generally employed and is applicable to all processes, chemical or physical, but in a closed system.

--- Carnot Cycle (5 or full 10 marks)

--- First law of Thermodynamics

Statement: Energy can be neither created nor destroyed, it can only be transferred from one form to another.

Explanation: When a system having internal energy U1 absorbs energy q from it's surroundings, then a part of the absorbed energy is utilized in increasing the initial energy of the system to U2 and the rest of the energy is used in doing expansion work. Therefore the amount of heat energy absorbed is equal to the increase in the internal energy and the work done by they system.

Equation + 5 Cases:

---

Reversible + Irreversible processes

Processes can be classified into Reversible and Irreversible

Reversible: A process which takes place extremely slowly through a series of small steps in such a way that the direction of the process can be reversed at any instant by making small changes in the state of the system. At the initial, final, and all intermediate stages, the system is in equilibrium state.

Irreversible Processes: A process which is carried out rapidly from the initial to the final state in a single step. It cannot be carried out in the reverse order. The system is in equilibrium at the beginning and at the end, but not at the points in between.

Differences between the two:

---

(5M)Def system + surroundings and diff types of system

System is the part of the universe which is under study and has definite boundaries.

Surroundings are the remaining part of the universe other than the system

The surroundings are limited to the immediate vicinity of the system.

ex: When studying a glass of water, water is the system, glass is a boundary, and the area around the glass of water is the surroundings.

There are a few types of systems depending on the nature of boundary: - Real System - Ideal System - Open System - Closed System - Isolated System

Open System: - The boundary is open and not insulated - Therefore an open system is one which can transfer both energy and matter to and from its surroundings. - ex: Hot water in a beaker placed on a table, the water vapor (matter) and heat (energy) both can escape from the beaker and be transferred to it's surroundings.

Closed System: - The boundary is closed and not insulated - Therefore a closed system is one which cannot transfer matter but can transfer energy to and from it's surroundings. - ex: Hot water in a closed container, the water vapor (matter) can not escape the system, however the heat (energy) can transfer through the walls of the container to the system's surroundings.

Isolated System: - The boundary is closed and insulated - Therefore an isolated system is one which cannot transfer either matter nor energy to and from it's surroundings. - ex: Hot water in an insulated thermos, neither the water vapor (matter) nor heat (energy) have a chance to escape the system.

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Process and Types

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State and Path Functions

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Joule's Law

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Work Done in Isothermal Reversible Expansion of Ideal Gas

[solqrays]

absolutely homophobic how i have to do a binomial math test AND study gibbs free enthalpy on my birthday

[camuslvr]

You ever think about how the universe is already dead? Not in the poetic sense, not in some grand metaphor about human decay—literally dead. Just hasn’t finished twitching yet. See, entropy doesn’t stop. It doesn’t slow down. Everything that burns cools, everything that moves stops, and one day, every star that ever lit up the void is gonna gutter out like a cigarette in an ashtray. That’s heat death. The final silence. The end of everything.

And it’s not some distant, hypothetical horror. It’s happening right now. You feel it in your bones, in the way your body breaks down a little more every day. That ache in your joints, the way your memories slip through your fingers like sand—that’s entropy, man. That’s the same law that’s gonna tear the universe apart, working its way through you on a smaller scale. Every living thing is just a temporary structure, an arrangement of matter pretending it has permanence.

Heat death isn’t just an end. It’s the end. The final state of everything. People think of death as something with edges, something with borders—the moment your heart stops, the second the light leaves your eyes. But that’s a small death. That’s just biological failure. Heat death is bigger. More absolute. It’s not just the death of living things, or planets, or stars. It’s the death of difference.

Entropy, mathematically speaking, is a measure of disorder—more precisely, it’s the number of microstates that a system can occupy.

S = k_B ln(Ω)

Where S is entropy, k_B is Boltzmann’s constant (1.38 × 10⁻²³ joules per kelvin), and Ω is the number of possible microscopic configurations of a system. That’s the math of inevitability, right there. Because as a closed system progresses, it moves toward higher Ω, higher disorder. More ways to arrange itself. That’s why you can’t unburn a fire, why you can’t unscramble an egg—because those higher entropy states vastly outnumber the lower ones. The universe doesn’t ‘prefer’ chaos, it just follows probability. And the probability of the entire universe spontaneously reorganizing itself into something structured again? Functionally zero.

Now, extend that to a cosmic scale. The universe right now is a nonequilibrium system—it’s full of energy gradients. Hot stars, cold space. Galaxies spinning in the vast dark. But that won’t last. Every time a star burns, it’s not just producing heat and light. It’s spreading energy out, making it less usable. That’s what free energy is—energy that can still do work. Once energy spreads out evenly, once everything is the same temperature, there’s no gradient left. No work. No structure.

ΔG = ΔH - TΔS

Where G is free energy, H is enthalpy (total energy), T is temperature, and S is entropy. You see that negative sign? That’s the kicker. As entropy (S) increases, the ability to do work decreases. The universe isn’t just dying—it’s fading. Every action, every reaction, is just one more step toward equilibrium, which is just another way of saying ‘universal heat death.’

It’s not an explosion. It’s not fire or collapse. It’s just everything slowing down. Cooling. Spreading out. Until every last subatomic interaction ceases, not because something stopped it, but because there’s simply nothing left to move. No energy left to transfer. No gradients. No contrast.

And here’s the part that’ll keep you up at night: It’s irreversible. The moment the universe started, the moment that first asymmetry emerged, this was always the final destination. You can’t stop it. You can’t fight it. You can’t invent some last-minute technological miracle to turn back the thermodynamic clock. There’s no equation that undoes entropy. The only way to reset the system would be to violate the laws of physics themselves.

So when the last remnants of existence flicker out—when the black holes evaporate, when the last protons decay, when even fundamental particles stretch into meaningless diffusion—that’s it. No afterimage. No memory. Just perfect, absolute nothing.

Because everything, everything that’s ever happened, has only happened because of contrast. Hot and cold. Light and dark. Order and chaos. Without that, without imbalance, nothing can exist. No movement. No thoughts. No matter shifting from one state to another. Just a uniform, static void stretched so thin that reality itself stops functioning. You can’t even call it blackness, because blackness implies the possibility of light. You can’t even call it silence, because silence needs something to compare itself to. Heat death is worse than destruction. It’s the absence of destruction. No fire, no explosions, no final moment. Just an infinite suffocation.

No memory of what came before. No last observer to bear witness. No evidence that there was ever such a thing as ‘something.’ Just an infinite, frozen void stretching in all directions, unchanging, unbroken.

And yet, here we are. Waking up. Pouring coffee. Loving people. Building things. We pretend we matter, because the alternative is realizing we were ghosts the whole time—just flickers of heat burning themselves out in a universe that’s already gone cold.

Maybe that’s all we are. Just sparks flying off a dying flame, burning bright for a second before the darkness swallows us whole.

[tenth-sentence]

For similar reasons, when ∆H and ∆S are both negative, ∆G will be negative (and the change spontaneous) only at low temperature:

∆G = (-ve) - (-ve) = (-ve) or (+ve)

"Chemistry" 2e - Blackman, A., Bottle, S., Schmid, S., Mocerino, M., Wille, U.

[jarviscodinghub]

Phys 362 Homework 12 Solved

1 Gibbs free energy and thermodynamic derivatives a) Starting with G = E − T S − PV, express dG in terms of dT and dP and use the result to express S and V in terms of derivatives of G (remember to indicate variables in the parentheses subscripts). b) Use the second derivative rule to show that ! ∂S ∂P ” T = − !∂V ∂T ” P . 2 Enthalpy and thermodynamic variables a) Express dH in terms of dP, dS…