Thermodynamics - Science topic

...the very words you use ('large heat source') contradict what you say. There's a third very definite equation that stands behind it.

Jugen Weippert, Thanks for the copy of Theory of regelation. I also need copy of PDF file first suggested by you. Our university does not subscribe it, Regards, Dulli,

Now let's discuss the relationship between Carnot efficiency and working fluid. Don't interfere with this issue by bringing downstream problems (be careful not to digress).

Carnot efficiency is not related to the working fluid, which means that the physical concept (Carnot efficiency) is detached from the physical entity (working fluid). The second law of thermodynamics cannot violate common sense. This mistake is that subsequent calculations of thermal work based on the second law of thermodynamics are also incorrect.

good answers above. the short answer is that you're failing to account for energy input requirements and losses at each stage of the process. the only way this works is if the net input is zero once all losses are accounted for.

It's a useful exercise to analyze the system to identify those elements, because they are key to any thermodynamic system design. And you aren't the first person to miss, or usually over/under-estimate such aspects of a thermodynamic system.

It's a bit illogical, I won't argue anymore. Carnot efficiency is independent of the working fluid -—— the second law of thermodynamics violates common sense and is lower than the average level of human intelligence.

It seems OK now. I will try to add data from other sources.

The second law is related to the impossibility of the perpetual motion of the second kind. Many people have tried to break this but so far nobody was able to achieve this. There is a nice book about these attempts:

Capek, Vladislav, and Daniel P. Sheehan. Challenges to the second law of thermodynamics. Dordrecht: Springer, 2005.

"In this volume we will attempt to remain clear on this point; that is, while the second law might be potentially violable, it has not been violated in practice."

You have been given the original formulations by the original authors of the second law and a logical deduction above. If your textbooks convert this into an odd quantitative statement, their authors or translators did a bad job.

The actual second law is, as shown in my previous post, a pretty basic statement, so what you are fighting against has actually never been the second law. i get that after all the time you wasted on this that is hard to grasp.

The quantified threshold (not prediction) of the second law with respect to the Carnot cycle is:

"Es gibt keine Wärmekraftmaschine, die bei gegebenen mittleren Temperaturen der Wärmezufuhr und Wärmeabfuhr einen höheren Wirkungsgrad hat als den aus diesen Temperaturen gebildeten Carnot-Wirkungsgrad."

There is no heat engine, which at given mean temperatures of of heat input and output provides a higher efficiency than the Carnot efficiency calculated from these temperatures.

Science speaks in mathematics, and to prove the correctness of the second law of thermodynamics, quantitative predictions must be made and consistent with experiments.

Only some misunderstanding of the 2nd law of thermodynamics can cause any paradox.

It simply states that any change of state of any stable system requires an expenditure of some amount of energy to account for the change.

Bo Miao The reason for the entropy increase of closed systems, in apparent conflict with the unitarity of Hamiltonian evolutions (preserving information) is the lack of information (relevant entropy) of macroscopic observers [1]. The interpretation of the second principle and the flow of time as illusions [2] amounts to a realist interpretation of physics in a deterministic universe endowed with objective laws and properties, denying the central role of the macroscopic observer and its only intersubjective macroscopic observables.

So, the thermodynamical statistical grid of reading of macroscopic observers (living beings) is the basis of irreversible evolutions, second principle of thermodynamics, irreversibility and indeterminism of quantum measurements and existence of traces of the past...

...hence of any information allowing us to ascribe physical laws and properties to the universe.

You will find more references concerning entropy, the second law of thermodynamics and the flow of time in the.

[1] , Am. J. Phys. 67, 1078 (1999)

[2] "The distinction between the past, present and future is only a stubbornly persistent illusion". Einstein, 1955, in a condolence letter to the family of his best friend and collaborator Michele Besso.

It is necessary to search for a thermodynamic data bank, a quick search brings

Reference Fluid Thermodynamic and Transport Properties Database (REFPROP)

But I do not know it it contains what you need. Otherwise search for papers, for example a quick search gives such a paper:

Safarov, Javid, Ulkar Ashurova, Bahruz Ahmadov, Elshan Abdullayev, Astan Shahverdiyev, and Egon Hassel. "Thermophysical properties of Diesel fuel over a wide range of temperatures and pressures." Fuel 216 (2018): 870-889.

The reversible voltage is measured at zero current. The actual decomposition voltage depends on the current density and contains contributions from electric resistance (Ohm's Law) and reaction kinetics

(so-called overvoltage) which are not covered by the 2nd Law. The difference of experimental decomposition voltages and reversible voltages is not an argument against the 2nd Law.

Your question can have a sens for a system at T=zero Kelvin. A molecule at this temperature don't oscillate but can spin in three sens or much more for a Universe with D-spatial dimensions.

Thank you. Your answers clearly demonstrate your level of discussion.

It is necessary to understand what an algorithm to compute equilibrium composition fits your needs. Is carbon considered as pure phase (one-component system) or as solid solution? Would be enough to consider the gas phase as an ideal association solution (each reacting component in the gas phase is described by mu = mu_0 + RT ln p_i).

Provided that the carbon is pure phase and the gas could be modeled as an ideal association solution, the best algorithm is the VCS algorithm from the book:

Chemical Reaction Equilibrium Analysis: Theory and Algorithms, W. R. Smith and R. W. Missen

I have used it in 1990-ies and this is the best algorithm to compute the equilibrium composition in this case. I have a code (TDLIB library) but it is rather old (from 1990-ies), no GUI, command-line only.

FactSage is designed for more complicated problems - computing phase diagrams when solution models are more complicated. Most solid solutions cannot be treated as an ideal association solution. This also makes the computation of equilibrium composition much more complicated - you need specialized algorithms.

By the way, I have checked Thermocalc. It still exists and it is similar to FactSage. It is written on the web-site that they offer The Free Educational Package.

Well, you have to check if the VCS algorithm is enough for you. If yes, this would be the best option. But I do not know if there is a nice GUI to use it nowadays.

Q=f (T) is the mathematical expression of "Carnot efficiency is only related to the temperature of the heat source". DQ=df (T) The second law of thermodynamics in mathematics (S) is derived from this and the definition of dQ cannot be changed arbitrarily.

In fact, the second law of thermodynamics changes the mathematical representation of dQ.

I have answered this question in your new post:

Bo Miao

Please have a look at the JANAF Thermochemical Tables. You fill find there entropies as a function of temperature tabulated for many substances. There is a lot of experimental research to this end. Do you mean that these all experiments are wrong? By the way, JANAF means Joint Army and Air Force, as this tables have been created to help to compute the rocket propulsion. Try to do it without the Second Law.

Your "comprehensive" article is based on the same false assumption as this one. Read Planck's original book, it's free at Project Gutenberg and, as you said yourself, Germany in general and Planck in particular are the original sources, so he knows what assumptions he made. If you base your life on bad resources and don't want to see that, that's not the fault of my countrymen...

The question highlights the difference between how Carnot efficiency is studied in the second law of thermodynamics and how engineers approach practical thermal systems.

calculation of decline of planet earth

"Be more complete and logical." – Well, your statements are incomplete.

"Don't solve problems just because of a few trendy terms." – Well, please remember Clausis' famous statement about entropy (cf-, e.g., https://en.wikipedia.org/wiki/Clausius_theorem); it is an inequality, so one has to consider two different cases.

YOU started this discussion; I'm not here to do your homework.

Focusing on generating energy from water by using ultra laser and electro mechanical to create vortex. its must be a chain reaction to reach to the level of high energy production

Hi there Leonard,

perhaps a possibility for you would be to present a selected number of your findings (not all) at a conference or in a journal paper? This would allow you to have some of your results reviewed and discussed while at the same time not giving everything away at once.

Let us know should you be releasing anything! I'd certainly be looking forward to it.

Best,

Julius

E is statistical to the same amount to which S is statistical, but since the trends in E can quite often be understood without explicitely invoking statistics, it is just skipped quite often in trend explanations.

E and S are both extensive quantities, so there is no spatiatemporal issue.

You are way too full of all kinds of misconceptions.

Start with a full intoductory physics

Series as the Berkly or Feyman.

Branko V. Mišković , agreed but my question was not about can it be done, it was about has anyone done it, or else I have to do it from scratch

No, that's the whole error in your argumentation which people have been trying to tell you over and over. That's only true for an ideal gas. You can integrate the energy balance for any non-ideal gas equation of state the same way one does for the ideal one and you will get a different (lower) efficiency.

If you truly have a textbook that claims η=1-T_A/T_B for a non-ideal gas, the textbook is shit.

As multiple people have already informed you, your schematic has the error that the material independent efficiency is not a fixed value, but constitutes a maximum that you cannot overcome independent of the material, so the contradiction is non-existent.

But thanks for the new entertainment.

Andrew Worsley Sergey Shevchenko Mazen Khoder Sagar Nanaso Salunkhe

In light of my recent research, detailed in the paper "Dark Matter is Just Gravity, Only Normal Matter is the Truth," published in the Indian Journal of Advanced Physics, I argue that what we refer to as dark matter can be explained through normal gravitational effects of ordinary matter. This perspective suggests that our current understanding of dark matter might be incomplete and that gravitational interactions could account for phenomena attributed to dark matter.

Furthermore, my forthcoming research extends this idea to dark energy, proposing that it too might be explained through phenomena we already understand but have not yet fully integrated into our models. By re-evaluating these cosmic forces through familiar physical principles, we might achieve a more unified understanding of the universe.

The idea of a single paradigm shift encompassing both dark matter and dark energy is intriguing. Such a shift could involve integrating these revised concepts into a broader framework that accommodates both gravitational effects and the expansive forces currently labeled as dark energy. This approach would not only address the mysteries of dark matter and dark energy but also potentially reshape our fundamental understanding of the universe.

I invite the ResearchGate community to discuss the potential for such a paradigm shift. Could integrating new findings on dark matter and dark energy lead to a more comprehensive model of the universe? What would such a unified framework look like, and how might it impact our current theories?

The blackbody cavity filled with CO₂ gas. This situation introduces additional complexities to the standard blackbody radiation model, which is typically based on an idealized cavity with no interactions with gases or other materials inside it. Here are some points to consider:

Blackbody Radiation and Planck's Law

Influence of CO₂ Gas in the Cavity

Modified Spectrum

Understanding the Deviation

By distinguishing between Zionist and Jewish people

My experience with ChatGPT (the paid version) was quite bad: it is impressive because it can now parse Word or pdf-texts, but it made a mess in interpreting my papers. It somehow always goes back to mainstream opinions on deep questions, and that does not help when you are working on something novel. Kindest regards - Jean Louis

Hi

I am currently studying thermoelectric devices, particularly the application of non-equilibrium thermodynamics in performance optimisation. Eager to connect with you!

Thanks

You are correct with your scepticism about the sometimes observed confusion between these terms in the context of HEAs and MEAs.

In metallurgy and generally in materials science, the stability of solid metallic solutions is governed by a complex interplay of thermodynamic factors when in equilibrium. Two key concepts in this context are configurational entropy (mixing entropy) and Gibbs free energy, which both indeed play crucial roles in stabilizing metallic solutions.

The configurational entropy, or mixing entropy, refers to the entropy change associated with the random arrangement of different atomic species in a solution, as described the partition function (Zustandssumme), i.e. the total multitude of states the atoms can be placed relative to each other. More of these possible arrangement lead to high mixing entropy. Essentially, this term thus quantifies the positional disorder introduced when different elements are mixed together in an alloy. For instance, in a binary alloy system with two elements, the configurational entropy increases as the atoms of these elements are mixed more randomly. The greater the randomness or disorder, the higher the entropy. This concept is indeed particularly significant in the formation of massive solid solutions high-entropy alloys (HEAs and MEAs), which are characterized by having multiple principal elements mixed in nearly equal proportions (in its original definition, which however is not always pertinent), resulting in an assumed high configurational entropy.

In stark contrast the term Gibbs free energy is a thermodynamic potential form that measures the maximum reversible work a system can perform at constant temperature and pressure. It serves as a comprehensive indicator of a system's stability, where a process or reaction is spontaneous if it leads to a decrease in Gibbs free energy. In metallic solutions, the free energy of mixing combines contributions from both enthalpy AND entropy to determine the overall stability of a material (i.e. it is inded NOT the entropy but Delta G that matters). The interplay between these factors dictates whether the alloy will form a stable solution or separate into different phases.

The stability of solid metallic solutions thus hinges ONLY on minimizing Gibbs free energy (all in equilibrium of course). High configurational entropy is only one of the factors that can promote stability by increasing the disorder within the alloy, thereby reducing the free energy. This reduction is crucial for maintaining a stable solution, especially in alloys with multiple elements. However, the enthalpy of mixing also plays a significant role as you correctly elude to. The enthalpy of mixing is the heat absorbed or released when different atoms mix (related to their bond strength). If the interactions between unlike atoms (those of different elements) are more favorable than those between like atoms (those of the same element), the enthalpy of mixing is negative, further stabilizing the solution by lowering Gibbs free energy. Conversely, if the interactions between unlike atoms are less favorable, the enthalpy of mixing is positive, potentially destabilizing the solution by increasing Gibbs free energy.

You are therefore indeed correct that enthalpy contributions also significantly affect the phase behavior and stability of metallic alloys. Depending on whether the enthalpy of mixing is positive or negative, various scenarios can arise. If the enthalpy of mixing is negative and sufficiently large, the alloy forms a completely miscible solid solution across all compositions, as the attractive interactions between different atoms dominate. A small positive enthalpy of mixing can result in partial solubility, where the alloy exhibits miscibility gaps, leading to phase separation at certain compositions and temperatures. A large positive enthalpy of mixing leads to immiscibility, causing the elements to segregate and form distinct phases rather than a solid solution. Additionally, alloys can exhibit ordered structures at lower temperatures and disordered solid solutions at higher temperatures. This transition is driven by the competition between the enthalpic preference for ordering and the entropic gain from disordering.

It must also be noted (and s sometimes overlooked in this field) that - apart from configurational entropy terms - also other types of entropy can influence the stability of metallic solutions. Vibrational entropy, associated with atomic vibrations in the lattice (use e g Debye theory), increases with temperature and can affect phase stability. High vibrational entropy can stabilize certain phases at elevated temperatures. Electronic entropy arises from the distribution of electrons among energy levels. It is generally small compared to configurational and vibrational entropy but can be significant in materials with complex electronic structures. Magnetic entropy, relevant in alloys with magnetic elements, is related to the alignment of magnetic moments and can influence phase stability, particularly in magnetic transitions.

The stability of solid metallic solutions thus indeed results from the intricate balance between configurational entropy and Gibbs free energy, with significant contributions from enthalpy and other forms of entropy. High configurational entropy favors stability by increasing disorder and lowering free energy. The enthalpy of mixing, depending on its sign and magnitude, can either promote or hinder the formation of stable solutions. A thorough understanding of these thermodynamic principles is essential for designing advanced materials with desired properties and stability.

I attach some papers where I also tried to disentangle these contributions a bit, trying to show that the design of HEAs (and related) is indeed NOT a single facetted (mixing entropy-focussed) thermodynamic task.

Good luck!

The most suitable property package for separating a mixture containing is the NRTL (Non-Random Two-Liquid) activity coefficient model

· Thermodynamic Modeling of Aqueous LiCl, LiBr, LiI, and LiNO3 Solutions. https://doi.org/10.1016/j.fluid.2020.112914.

· A computationally effective formulation of the thermodynamic properties of LiBr-H2O solutions from 273 to 500 K over full composition range. https://doi.org/10.1016/J.IJREFRIG.2005.10.007.

· Thermodynamic properties of lithium bromide-water solutions at high temperatures. https://doi.org/10.1016/S0140-7007(00)00039-6.

· Improved thermodynamic property fields of LiBr-H2O solution. https://doi.org/10.1016/S0140-7007(99)00076-6.

· A Gibbs energy equation for LiBr aqueous solutions. https://doi.org/10.1016/J.IJREFRIG.2005.05.006.

· A NEW MODEL FOR DETERMINING THE THERMODYNAMIC PROPERTIES OF LiBr-H2O SOLUTION. gazi university journal of science, 17, 101-110.

Bo Miao

The concept of perpetual motion machines has fascinated scientists and inventors for centuries. However, it’s essential to understand that true perpetual motion machines are impossible due to the laws of thermodynamics. Let’s break down the scenario you’ve described and address the researcher’s question.

A perpetual motion machine is a hypothetical device that can perform work indefinitely without an external energy source. Such a machine would violate the laws of thermodynamics. The laws of thermodynamics apply universally, regardless of the system’s size or complexity. There are three types of perpetual motion machines:

Machines of the First Kind: These machines produce work without any energy input. They violate the first law of thermodynamics. Machines of the Second Kind: These machines spontaneously convert thermal energy into mechanical work without any input. While they don’t violate the conservation of energy, they do violate the second law of thermodynamics. Machines of the Third Kind: These machines continue to be in motion forever due to inertia, but they cannot exist in practice due to unavoidable dissipation (e.g., friction).

In your scenario, you have two containers (A and B) separated by a transparent solid. Container A contains CO2 at a concentration of 3 mol/L, while container B contains CO2 at 1 mol/L. Radiation energy is transferred from container A to container B. The temperature in container B (Tb) is higher than in container A (Ta).

You are interested in whether this setup could lead to a perpetual motion machine based on radiation. Unfortunately, this scenario does not solve the problem of perpetual motion. Here’s why:While radiation is a long-range interaction, it still obeys the laws of thermodynamics.

The second law of thermodynamics states that the entropy (disorder) of an isolated system tends to increase over time. In other words, energy spontaneously flows from hotter regions to cooler regions. In your setup, container A (with higher concentration) will naturally radiate energy to container B (with lower concentration), resulting in cooling of container A. This process cannot continue indefinitely without an external energy source.

The temperature difference (Tb > Ta) does not change this fundamental limitation.

Even if you were to achieve perfect control over radiation, the energy stored in the CO2 concentrations would eventually be exhausted. Perpetual motion machines remain theoretical and cannot be commercialized because they violate the laws of thermodynamics.

In summary, while the concept of using radiation for energy transfer is intriguing, it does not provide a solution to perpetual motion. Researchers should focus on practical and sustainable energy solutions that adhere to the fundamental principles of physics

Everyone can compare and read to see who is bragging.

The second law of thermodynamics is a fundamental principle in physics that describes the direction of natural processes and sets limitations on the efficiency of heat engines. It can be stated in various forms, but one common statement is that in any spontaneous process, the total entropy of a closed system plus its surroundings will increase.

While the second law has been extraordinarily successful in explaining and predicting the behavior of systems, it's worth noting that there can be challenges in applying it universally to every situation, particularly at the microscopic level or in systems that are far from equilibrium.

One reason for potential inconsistencies with experiments could be the difficulty in precisely defining and measuring quantities like entropy, especially in systems with many particles or complex interactions. Entropy is a measure of the disorder or randomness of a system, and its calculation often relies on statistical mechanics, which involves making statistical assumptions about the behavior of particles.

Additionally, at the microscopic level, there are instances where the behavior of individual particles may seem to violate the second law, leading to discussions about statistical fluctuations and the arrow of time. However, these apparent violations typically occur on very short timescales or involve very small systems and do not contradict the overall validity of the second law for macroscopic systems.

As for symmetry and conservation, the second law doesn't strictly require these properties. Symmetry and conservation principles are important in physics, but the second law is more about the directionality of processes rather than symmetries or conservations.

Overall, while the second law of thermodynamics has been extremely successful in describing the behavior of macroscopic systems, there are still ongoing debates and research efforts to understand its implications at smaller scales or in more complex systems. These discussions often lead to deeper insights into the nature of thermodynamics and the behavior of physical systems.

Dear Arieh,

Thank you for your insightful response and for highlighting the importance of context when discussing entropy. Your point about entropy being a state function, determined for a macro-system at equilibrium, is well taken. I appreciate the opportunity to further clarify and expand on my position regarding entropy and the Arrow of Time.

You are absolutely correct that entropy is a state function, meaning its value depends on the state of the system and not on the path taken to reach that state. This foundational concept is crucial in thermodynamics and helps avoid misunderstandings about entropy’s behaviour.

I agree that it is essential to specify the system and the process when discussing whether entropy increases. Traditional thermodynamics tells us that for isolated systems, entropy tends to increase, leading to the Second Law of Thermodynamics. However, recent research by me, including the study I referenced by myself, challenges this view by suggesting scenarios where entropy remains constant, particularly in non-isolated systems or when considering quantum effects.

The latest research I mentioned posits that under certain conditions, entropy does not necessarily increase and could be constant. This assertion arises from the exploration of systems beyond the classical isolated frameworks typically considered. The implications of these findings are profound, potentially altering our understanding of thermodynamic processes, particularly in complex or quantum systems.

Regarding the Arrow of Time, the traditional view holds that it aligns with the increase of entropy, thus giving time a direction from past to future. However, the concept of T-symmetry (time-reversal symmetry) suggests that the fundamental laws of physics should remain invariant if time were reversed. The new findings propose that if entropy can be constant, then the Arrow of Time might be T-symmetric, challenging our conventional understanding and opening new avenues for theoretical exploration.

I would love to delve deeper into the specifics of the system and processes under which these new entropy findings were derived. Perhaps we can examine particular case studies or models where entropy behaves differently than traditionally expected. This could lead to a richer understanding of both entropy and the Arrow of Time.

Thank you again for your thought-provoking response. I look forward to continuing this stimulating discussion and exploring these groundbreaking ideas further.

Best regards,

Sandeep

Solution to this one:

So once more you have shown that if you violate the first law, you also violate the second law.

The second law of thermodynamics contradicts itself. Scientists are also addicted to the surface of experience.

Galileo's introduction of Aristotle's theory of falling is contradictory, and Aristotle's theory of falling is ineffective.

Lucas Lima

Your case is similar to the thermodynamics of the dissolution of hydrocarbons in water. This is due to quantum phenomena in the process. In some cases, it is impossible to formulate a theory of thermodynamics without the concept of a microstate. Microstates are best understood in terms of quantum states S = − Tr ρ log ρ , where Tr -trace, ρ is the density matrix. In linear algebra trace square matrix A, denoted tr(A). You calculated thermodynamics within the framework of classical thermodynamics. It is necessary to take into account quantum phenomena.

The total pressure drop in a Stirling engine is calculated by summing the pressure drops at the hot and cold ends of the engine. The pressure drop at the hot end occurs as the working fluid expands due to heat absorption, while at the cold end, it happens as the fluid contracts and cools. Maintaining an appropriate pressure difference between the hot and cold ends is crucial for efficient engine operation. Calculating the total pressure drop requires considering factors such as temperature, volume of the working fluid, and engine design specifics.

Dear Bo Miao ,

I understand your concern, as at first glance, it seems like there are more equations than variables, which could imply that there is no solution. However, upon a more rigorous mathematical analysis, I believe the second law still holds in this case.

In your system, you have CO, O2, CO2 gases, and solid carbon (C) with three chemical equilibrium reactions: 2CO + O2 ⇌ CO2, C + O2 ⇌ CO2, and C + CO2 ⇌ 2CO. The corresponding equilibrium equations are ρ_co^2 / (ρ_co2 * ρ_o2) = K1, ρ_co2 / ρ_o2 = K2, and ρ_co^2 / ρ_co2 = K3. Additionally, you have an element conservation equation, 0.5ρ_co + ρ_co2 + ρ_o2 = A, where A is the average concentration of O2.

The equilibrium constants K1, K2, and K3 are not independent variables. They are related to the Gibbs free energy change (ΔG) of each reaction at a given temperature T by the equation ΔG = -RT ln(K), where R is the gas constant. Therefore, only two of the three K values are independent.

We can rewrite the equilibrium equations in terms of ΔG: ΔG1 = -RT ln(K1) = -RT ln(ρ_co^2 / (ρ_co2 * ρ_o2)), ΔG2 = -RT ln(K2) = -RT ln(ρ_co2 / ρ_o2), and ΔG3 = -RT ln(K3) = -RT ln(ρ_co^2 / ρ_co2). The sum of the ΔG values for the three reactions must be zero, as the overall process is at equilibrium: ΔG1 + ΔG2 + ΔG3 = 0. Substituting the expressions for ΔG1, ΔG2, and ΔG3, we get -RT ln(ρ_co^2 / (ρ_co2 * ρ_o2)) - RT ln(ρ_co2 / ρ_o2) - RT ln(ρ_co^2 / ρ_co2) = 0.

This equation, along with the element conservation equation, forms a system of two equations with three variables (ρ_co, ρ_co2, ρ_o2). While this system is underdetermined, it does not necessarily mean there is no solution or that the second law of thermodynamics is violated. The second law states that the entropy of an isolated system at equilibrium is maximum, and the change in Gibbs free energy is zero. The equilibrium state of this system, if it exists, would satisfy these conditions.

The apparent contradiction between the number of equations and variables in this chemical system does not inherently violate the second law of thermodynamics. The equilibrium constants are related through the Gibbs free energy, reducing the number of independent equations. The system may have an equilibrium state consistent with the second law, even if it is not uniquely determined by the given equations alone. Additional constraints, such as the positivity of concentrations or the minimization of Gibbs free energy, could potentially lead to a unique solution.

The second law of thermodynamics is a fundamental principle that has been extensively verified experimentally. I think it is important to critically examine such principles, but the presented argument does not provide sufficient evidence to overturn this well-established law.

Best,

Alessandro Rizzo

these preprint papers claimed reversing entropy by mixing Raoult's law with osmosis principle and extended Gibbs Donnan Equilibrium .

What do you think about this novel approach?

Title of the papers:

Experimental Demonstration of Energy Harvesting by Maxwell's Demon Device

DOI: 10.20944/preprints202403.1698.v1

....

An Autonomous Mechanical Maxwell's Demon

DOI: 10.14293/S2199-1006.1.SOR-.PP5S6NK.v1

Based on findings, the aim of congruence between gravity and thermodynamics is more of an inferential tool rather than an epistemological completion. Since it helps us understand the relationship between these two fundamental theories and explore the connections between gravity and the behavior of thermodynamic systems.

So what is the problem? You obtain more than one solution; one of them has the lowest Gibbs energy (assuming that you keep the pressure and the temperature constant), and that is the stable state.

Changing the conditions, i.e., adding a mixture component, can eventually make the system jump to another stable state. This phenomenon has been described, for instance, for the ammonia synthesis from hydrogen and nitrogen.

There is no problem with the 2nd Law.

我觉得外星人来锣

Hello! Cyclic voltammetry is a powerful electrochemical technique that provides a wealth of information about the thermodynamic, kinetic, and mechanistic characteristics of electrode reactions. By carefully analyzing the cyclic voltammograms obtained from this technique, researchers can gain valuable insights into the fundamental nature of these reactions.

One of the key thermodynamic properties that can be determined from cyclic voltammetry is the formal redox potential of the electroactive species. This is obtained by finding the midpoint potential between the oxidation and reduction peaks in the voltammogram. Additionally, the number of electrons transferred in the redox process can be calculated from the peak potential separation, while the reversibility of the reaction can be evaluated based on the peak current, peak potential, and half-peak potential.

Kinetic information can also be gleaned from cyclic voltammetry. The rate of electron transfer and the overall reaction kinetics are reflected in the size, shape, and position of the peaks in the voltammogram. For example, in a reversible system, the ratio of peak currents for the forward and reverse scans should be close to 1. Moreover, for a diffusion-controlled process, the peak current is directly proportional to the square root of the scan rate.

Cyclic voltammetry is also a valuable tool for elucidating the mechanistic details of electrode reactions. By examining the overall shape of the voltammogram, researchers can determine the number of steps involved in the redox process. The presence of adsorbed species on the electrode surface can be detected by comparing voltammograms obtained at different scan rates. Comparing the voltammetric response on different electrode materials can provide insights into electrode-specific reactivity. Furthermore, coupling cyclic voltammetry with other techniques, such as impedance spectroscopy, can yield additional mechanistic information.

Thus, cyclic voltammetry is an indispensable technique for probing the thermodynamics, kinetics, and mechanism of electrode reactions. By carefully examining key parameters such as peak potentials, peak currents, peak shapes, and their variation with scan rate, researchers can gain a deep understanding of these complex processes. This knowledge is crucial for developing new electrochemical technologies and optimizing existing ones.

The formula change in S = dQ/T refers to a particular case, that of simple thermal heating. The expansion of an ideal gas into a vacuum involves no change in energy, so this formula does not apply to that case.

Hello, my most significant critique of your book is that it doesn't explain why Europeans would oppress and subjugate non-Europeans if they valued racial diversity. Why would an ethnic group that views itself as superior to other ethnic groups strive for systems that are inclusive for all races? By the way, I'm Mr. Landol. I have a master's degree, not a PhD.

Bo Miao

i assume this is genuine question you have raised;

leading with that,

The statement that gas radiation and absorption could invalidate the Second Law of Thermodynamics is a misunderstanding of how thermodynamics and heat transfer operate. The Second Law of Thermodynamics, in its simplest form, states that in any closed system, the entropy (a measure of disorder or randomness) tends to increase over time unless energy is put into the system to maintain or decrease entropy. This law is one of the fundamental principles underlying much of physics and engineering and is observed to hold true in countless experimentation.

Regarding the specific points raised:

1. Gas Radiation and Absorption

it true that gases at different locations can absorb radiation differently and this can lead to temperature differences across a system. However, this process does not violate the Second Law of Thermodynamics. The law does not imply that temperature differences cannot exist or that they cannot change; it primarily concerns the overall entropy of a closed system. In the context of gas radiation, the energy transfer through radiation leads to changes in temperature and can drive processes that increase the system's overall entropy.

2. Temperature Differences and Entropy

The creation of temperature differences through radiation absorption and emission is a part of how heat transfer operates in the universe. These processes, including conduction, convection, and radiation, are mechanisms for energy distribution and do not inherently contradict the Second Law. The entropy increase or decrease in a particular part of a system does not imply a violation of the law as long as the total entropy of the closed system, when considering all interactions, does not decrease.

3. Perpetual Motion Machines

The idea of a perpetual motion machine—a machine that can operate indefinitely without an energy source—is a concept that violates the First and/or Second Law of Thermodynamics. Despite extensive theoretical and experimental exploration, no such machine has been created or observed to exist. The Second Law, among other principles, indicates why perpetual motion machines are not feasible.

I did struggle to understand the non sequiator in your comments, as per the suggestion that belief in such devices is contingent on catastrophic events like nuclear war…it is not grounded in scientific reasoning.

Scientists rely on empirical evidence and theoretical consistency to validate or refute theories. The Second Law of Thermodynamics is supported by a vast body of evidence and theoretical understanding, making it one of the cornerstones of physical science. While scientific understanding evolves with new discoveries, any new theory or observation that appears to contradict well-established laws like the Second Law of Thermodynamics requires rigorous scrutiny, experimental validation, and theoretical explanation within the broader framework of physics.

best

H

The Gibbs free energy of formation at 298K for silver oxide is -11.1kJ/mol, so it is weakly exergonic and the answer to your question is "yes, but extremely weak".

I used the mass flow rate of the ORC*(enthalpy at exit-enthalpy at inlet)

In Gaussian, Temperature= … imposes the temperature of thermochemical calculations (https://gaussian.com/temp/). By definition ZPE is not dependent on the temperature. What changes by increasing T is not ZPE, but the population of higher vibrational states of the GS. See K. K. Irikura "Experimental Vibrational Zero-Point Energies: Diatomic Molecules" J. Phys. Chem. Ref. Data 36(2), 389, 2007.

Three formulas can explain that gas radiation cannot reach thermal equilibrium, and the second law of thermodynamics is incorrect.

L.D. Edmonds All measurement "devices" collapse quantum wavefunctions by putting the quantum system that is being measured in contact with the "devices" thermal bath. The quick answer to your question is the thermal bath entropy of any measurement "device."