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# Thermodynamics - Science topic

Thermodynamics is the branch of natural science concerned with heat and its relation to other forms of energy and work.
Questions related to Thermodynamics
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Scientists have abandoned testing the correctness of Carnot efficiency (1-T1/T2) (Method A), instead of using theory to aggregate experimental data and achieve a compromise between theory and experiment (Method B).
If scientists rigorously tested the Carnot efficiency, the second law of thermodynamics would have been over long ago.
Abandoning the second law of thermodynamics is the only option. Repairing and repairing cannot solve the problem.
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Radiation is joking with the Second Law of Thermodynamics, and scientists have been tricked. Below is a comparative description.
A--Output of the second law of thermodynamics
1A, Second Law of Thermodynamics: Heat cannot spontaneously transfer from low to high temperatures.
1B, thermal radiation: Low temperatures can radiate to high temperatures, while high temperatures can radiate to low temperatures.
2A, scientists bet on the heat transferred by radiation: q (T1_to_T2)>q (T2_to_T1), where T1>T2
2B, actual intensity of thermal radiation:
q (T1_to_T2)=q (T1, n1); Q (T2_to_T1)=q (T2, n2)
n1, n2- Number of internal radiation structures of heat sources 1,2. Specific examples: 1 is helium, 2 is CO2, and n1 will be less than n2 In this case,
q(T1_to T2)<q (T2_to T1) where T1>T2
3A,Scientists from the 17th to 18th centuries believed that knowledge like 2A could be forgiven.
3B, scientists in the 21st century still believe in knowledge like 2A, which would be a bit foolish.
4B, see simulation case (image) for details
The provided text deals with an apparent contradiction between the Second Law of Thermodynamics and the behavior of thermal radiation. To resolve this contradiction, the focus is on how the internal structures of heat sources impact the intensity of thermal radiation. While the Second Law of Thermodynamics (1A) applies to the transfer of heat between low and high temperatures, thermal radiation (1B) exhibits a different behavior where heat can spontaneously transfer between low and high temperatures and vice versa.
The comparison between 2A and 2B relies on the actual experimental performance of heat transfer through radiation. In the case of actual thermal radiation (2B), it becomes evident that the intensity of radiation depends on the internal radiation structures of heat sources. While the assumptions of scientists in earlier centuries (3A) might be forgivable due to limited knowledge, contemporary adherence to such beliefs (3B) could be considered less justified given the advanced understanding of radiation and its dependence on internal structures, as illustrated in the comparison between 2A and 2B.
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Abstract: The radiation power f * T ^ 4 [W/m3], 1.2 * f * T ^ 4 [W/m3], absorption rates of 0.2 [1/m], 0.1 [1/m], wall temperature of 293.15K, emissivity=0 in two calculation domains, and there is a temperature difference in the calculation system: the temperature in areas with strong radiation is lower, while the temperature in areas with strong radiation is higher, with a temperature difference of more than 10K. Both the 0th and 2nd laws of thermodynamics are incorrect.This phenomenon objectively exists: for example, under the same conditions, the radiation power of carbon dioxide and water vapor will be greater than that of oxygen and helium. This asymmetric radiation condition is arbitrarily set in engineering and is constrained by the 2nd and 0th laws of thermodynamics.
See picture for details
The thermal conductivity of two media is equal to 1 [w/m2K].
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There is no equilibrium state in an isolated system, and the second and 0th laws of thermodynamics fail.
2. Nonequilibrium fluctuation test
The helium and carbon dioxide in the container are mainly carbon dioxide in the lower part of the container, and are near its critical point, so the fluctuation energy of the gas is large. The upper half of the container is mainly composed of helium, which is a conventional gas. The fluctuation energy is small. The fluctuation energy of the lower part will be transferred to the upper part, which will destroy the thermodynamic equilibrium probability distribution of the upper and lower parts of the container. The average internal energy of the lower gas is converted into fluctuation energy, while the fluctuation energy of the upper gas is converted into average internal energy, resulting in an increase in the temperature of the upper helium and a decrease in the temperature of the lower carbon dioxide. The thermal equilibrium cannot exist, and the 0th law and the 2nd law of thermodynamics fail at the same time.
The difficulty of this experiment is average, and if possible, it can be done to see the mutual influence of fluctuations.
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All thermodynamics textbooks say that the Clausius formulation and the Kelvin formulation are equivalent to the entropic formulation - and this is proven. Meanwhile, there is only one proof scheme, which turns out to be wrong. The matter is serious, so at this stage there is no point in going further with the description.
Dear Prof. Grzegorz M. Koczan
Interesting question.
What about the use of the Statistical Microscopic Thermodynamics to formulate the second law using the canonical ensemble, as it is done in the classical textbook by Prof. Frederick Reif:
"Fundamental of Statistical & Thermal Physics" (1965) by Prof. F. Reif Mc Graw-Hill"
Kind Regards.
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Hello all dear
A solvent enters a vessel at a temperature of 100 °C and turns into solvent vapor at a temperature of 150 °C.
I want to know if this analysis I am doing is correct?
The 100 °C solvent inside the vessel becomes a 140 °C solvent and the amount of heat it absorbs due to the increase in temperature is calculated from Q=mcdT.
140 °C solvent turns into 140 °C solvent vapor and the amount of heat that is absorbed only to change the phase is calculated from the enthalpy of vaporization formula.
Then, the 140°C solvent vapor is converted to 150°C solvent vapor, and the amount of heat absorbed to increase the temperature of the vapor is also calculated from the Q=mcdT.
Is this analysis correct?
1. Experimental measurement: The most accurate way to determine the enthalpy of vaporization is through experimental measurements using calorimetry. This involves measuring the heat transfer during the phase transition from liquid to vapor. By measuring the temperature change and known masses of the substance, the enthalpy of vaporization can be calculated using the equation Q = m × ΔH, where Q is the heat transferred, m is the mass, and ΔH is the enthalpy of vaporization.
2. Trouton's rule: Trouton's rule is an empirical rule that provides an estimate of the enthalpy of vaporization based on the boiling point of a substance. According to Trouton's rule, the enthalpy of vaporization (ΔHvap) is approximately a constant value of around 88 J/mol·K. It can be expressed as ΔHvap ≈ R × Tb, where R is the ideal gas constant and Tb is the boiling point in Kelvin.
3. Group contribution methods: Group contribution methods are used to estimate the enthalpy of vaporization based on the molecular structure of the substance. These methods assign specific contributions to different functional groups or molecular fragments and sum them up to estimate the overall enthalpy of vaporization.
4. Semi-empirical correlations: Various semi-empirical correlations exist to estimate the enthalpy of vaporization based on molecular properties, such as molecular weight, critical temperature, or critical pressure. These correlations are typically based on regression analysis of experimental data and provide reasonable estimates for a wide range of substances.
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I would like to obtain a design program, a free version, available to engineering students for a graduation project. The graduation project is a simple gas cycle and exhaust from it enter to HRSG . Therefore, I am looking for a program to design the HRSG , dDetermine the number and size of tubes in each part of hrsg ( evaporator, economizer, super heater ), and connect it through the program to the gas turbine. Thank you for participation.
ThermoC (http://thermoc.uni-koeln.de) is not a design program for machinery, but can produce thermodynamic data (including phase envelopes, adiabatic expansion curves, etc.) for real fluids (pure or mixtures). It can be used over the Internet or installed locally (free for academic users).
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Hello all dear
It happens at a constant temperature of 140(Tb)
The composition is similar to gasoline
Can you introduce an equation?
Dear Prem Baboo isn't this equation for pure substances?
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It is easier for scientists engaged in nuclear fusion to switch careers to permanent motion, so it is recommended to switch careers.
• The three formulas in the figure are the dynamic basis of this perpetual motion machine.
• The only difficulty is charge binding: the diffusion process of charges from A to B requires a constrained electric or magnetic field. The difficulty of this constraint is relatively small compared to nuclear fusion, and it is easy for them to switch to making perpetual motion machines. Suggest transitioning to nuclear fusion and engaging in perpetual motion machines.
• Although some progress has been made in nuclear fusion, there are still many technical challenges and high costs.
• There are various ways to implement perpetual motion machines, not limited to this model.
Dear Bo Miao ,
Interesting the idea you have realized. I am not familiar in this area, so for a better understanding.
the following questions would be asked:
You have the following interesting remark:
'The only difficulty is charge binding: the diffusion process of charges from A to B requires a constrained electric or magnetic field. The difficulty of this constraint is relatively small compared to nuclear fusion, and it is easy for them to switch to making perpetual motion machines. Suggest transitioning to nuclear fusion and engaging in perpetual motion machines.' - In the system, you can achieve this by using the metal bucket.
after the electrical current is switched off, what maintains the permanent magnetic or electric field ? Where will the system get the energy to do this?
By R, you maintain the electrical potential.
Regards,
Laszlo
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Hello Researchers,
I am trying to explain corrosion mechanisms in alloys through DFT. i wanna know which fundamental thermodynamic properties i need to calculate to explain corrosion in alloys.
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I'm thinking of evolution and if there is some end point?
Apologies for the confused question. I was equating organisation with complexity.
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1. The correctness of scientific laws depends on quantitative prediction and experimental compliance, rather than relying on life experience and engineering experience.
2. The two major expressions of the second law of thermodynamics are life experience and engineering experience. The core quantitative prediction is η= 1-T1/T2. The verification method is Method A in the figure (with quantitative prediction), but scientists extensively use Method B (without law prediction), indicating that seeking equilibrium in theory and experiment is actually cheating: concealing the inconsistency between the second law of thermodynamics and experiment. This violates scientific discipline and morality.
3. Scientists possess a large amount of data, and if they used Method A (which is in line with scientific discipline and ethics), the Second Law of Thermodynamics would have been shattered long ago.
Why do you children in computer science think that your logic symbols and diagrams have any meaning or relevance to this or any other world whatsoever? There is zero meaning or relevance to the diagram, deliberately shrouded with undefined symbols so as to impress and confuse.
I will state it clearly, 'Computer Science' is not a valid science. Science is defined as the study of nature. The invalid term, "computer science" is merely a mechanism of human language and thinking, and has nothing to do with nature, nor does any 'computer science' student have the ability to read the maths required to understand science. I have never encountered a 'computer scientist' who had the slightest clue what Physics is.
It is so far from meaningful that it is embarrassing to watch.
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I have two values of cp at 100 and 140 degrees
The most common approach to variation of Cp is a polynomial fit (keep the order low, not more than cubic), or for small ranges a simple linear fit is commonly used. Remember that extrapolation is always risky with curve fits. There are more complicated equations of state that are used in high precision work and extrapolate better, but these are rarely needed in practical problems.
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Comparison:
1）The first law of thermodynamics calculates the Carnot efficiency；
2）the second law of thermodynamics predicts: η= 1-T1/T2.
Method:
1）The first law: P=P (V, T), E=E (V, T) DE=Q-W==>η，Efficiency needs to be calculated and determined.
2）Second Law: Anti perpetual motion machine, guessing==>1-T1/T2.
Effect:
1）The first law: E, P, W, Q ，η of the cyclic process can be obtained,
2）Second Law: Only efficiency can be obtained：η= 1-T1/T2.
• The uniqueness of natural science requires scientists to make choices.
• The second law of thermodynamics can only yield a single conclusion: η= 1-T1/T2（Meaningless--- lacking support from E, P, W, Q results.）Like an island in the ocean.
Bo Miao: "The first law of thermodynamics calculates the Carnot efficiency" -- no, not at all. The first law only states that heat and work (i) are forms of energy, and (ii) they are the ways energy is transferred from one system to another. How could there be any efficiency included in this law? Please explain.
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• In the figure, one gas is an ideal gas (dE1/dV1=0) and the other is a real gas (dE2/dV2 is not equal to 0), which can achieve heat transfer from low temperature to high temperature without consuming external energy. This is the second type of perpetual motion machine.
• Real gas (dE/dV not equal to 0). This is the simplest middle school physics knowledge.Middle school physics knowledge can defeat the second law of thermodynamics. Isn't this very funny?
• This field will produce Nobel Prizes, welcome to join.
Simply insert the van der Waals real gas equation of state (or Redlich-Kwong or Virial ansatz, if you prefer those) into the dW equation. You will also get a dW that's not 0. This is a trivial operation.
Arbitrarily setting dW=0 for an isothermal (or adiabatic) process here is actually a violation of the first law of thermodynamics and I got the notion that you believe at least in this one, or has that changed?
So what you have demonstrated here is actually: if we violate the first law of thermodynamics, the second one is also useless. But since the first law is valid, your "proof" is invalid.
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Friends, I am using Gaussian 09 to calculate Bond dissociation energy (BDE). How to view the entropy of this molecule after optimizing its molecular structure
- How do I specify the position of a radical in the furane molecule (alpha C or beta C) in the Gaussian 09 input file?
- When we calculate the bond dissociation enthalpy (deltaH) of the bicycle molecule as 2,2' bifurane, is it correct to use the ground or transition state of this molecule as reactant?
- Is it necessary to reoptimize the product radical, or is SP sufficient?
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We cannot imagine the existence of classical and modern physics without Newton's second law in its general form.
Newton's second law is a hypothesis of universal law that does not need mathematical proof.
It is inherent in almost all theories of physics such as Hamiltonian and Lagrangian mechanics, statistical mechanics, thermodynamics, Einstein's relativity and even the QM Schrödinger equation.
The famous Potential plus Kinetic law of conservation of mechanical energy, inherent in most formulas of QM and classical mechanics, is a form of Newton's law.
We would like to see a rigorous proof of the famous E = m c ^ 2 without Newton's second law. [1].
Can Schrödinger's PDE replace Newton's law of motion?
1-Quora Q/A, Does Newton's law of motion agree with the special theory of relativity?
In a classical set-up I like to view Newton's 2nd Law written as F(x(t))/m = x''(t) as an axiom because in a way it defines a dynamical force F [maybe dependent on the position x(t) of the object]. It is successful because it leads for some simple cases to the "right" answer, e.g.
(i) Experiment 1: if the force F=const one obtains as solution x(t) = 0.5*(F/m)* t^2 + v_0*t +x(0) which already Galilei has observed.
(ii) Experiment 2: if you assume the gravitational force to be F(x) = g * M1 *M2 / x^2 you get indeed the observed elliptic orbits of the planets and the Kepler laws
This success was enough at the time of Newton to view it as a basic axiom from which you can derive everything, even the philosophical problem of determinism and the paradox of free will.
The big draw-back of Newton's 2nd Law was that it works well for dynamical forces but when coercive forces are coming into the game it gets rather nasty. The easy way out was indicated by d'Alembert with his "virtual displacements" and formalised by Lagrange who introduced generalised coordinates (which in a natural way include the information about coercive forces) and the variational principle of least action.
If you view the world from Karl Popper's critical rationalism philosophy then Newton's 2nd axiom is useful to us as long as it yields the right results observed in the experiments. However, when relativity or quantum effects are relevant, the Newtonian theory fails and needs to be replaced by something "better".
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When using Gaussian 16 to model a chemical reaction that occurred at 100 degrees Celsius with two reactants, should I include the temp=373 keyword during the thermodynamic calculations of species or during the transition state calculation? Additionally, if studying the reaction in a solvent, which dielectric constant should be considered? Dielectric constants can change with temperature, so how do I determine the appropriate value for the temperature at which the reaction occurred
You include the temperature=373 in the frequency calculations. You might want run your opt and freq in the same command line, so you need to write the opt freq temperature=373 .
Including solvent in calculations can be performed either along with optimization or you run your optimization in gas phase followed by a single point energy in solvent. If your system is small, I would rather perform all calculations in solvent. Choosing the solvent depends on the reaction condition; thus in which solvent your reaction is done you will then select the solvent based on that. Also, the temperature is based on the condition.
For example: #p opt freq m062x/def2tzvp scrf=(smd,solvent=acetone) temperature=373 test
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Quantum computers have not led to an increase in information entropy. The information theory of the second law of thermodynamics is deceptive.
Quantum computers have not led to an increase in information entropy. The information theory of the second law of thermodynamics is deceptive.
How do you know?
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• A perpetual motion machine is a concept of engineering and outcome. It plays a small role in the first law of thermodynamics, but in the second law of thermodynamics, perpetual motion machines have become the starting point of theory, greatly improving their status. When comparing the two, it can be found that the logic of the second law of thermodynamics is filled with experiential themes, lacking rational logic, and is a loss of the rational spirit of scientists.
• In practice, scientists extensively use method B in the figure to try to find a balance between theory and experiment. This kind of thing was originally invisible, but scientists treated it as a treasure. It's quite ironic.
• Originally a trial of the second law of thermodynamics, it has become a trial of scientists. I believe there will be a response from scientists.
Originally a trial of the second law of thermodynamics, it has become a trial of scientists. I believe there will be a response from scientists.
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I believe temperature T, pressure P and volume V are all measurable quantities. Entropy S is not measurable. Further, there is an uncertainty relation associated with temperature and energy. That is, temperature can only be measured by bringing a system into contact with another system of known temperature. However, energy can only be measured in an isolated system.
Perhaps, one way to meaningfully formalize the question is to start by postulating that temperature T, pressure P and volume V of any system are measurable using available metrology. Then, one possible formalization of the question is if the internal energy can be measured by measuring T, P or V of the original system or by measuring T, P or V of the result of a certain controlled interface (adiabatic mixing? mixing in a fixed volume?) of the original system with another, specially prepared system.
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The second law of thermodynamics is difficult to solve the phase transition equilibrium of capillaries!
See pictures and links for details:
Article 1: To solve the static equilibrium of capillary liquid level.
It is almost impossible to solve the phase transition equilibrium of the capillary liquid surface. This is a test for the second law of thermodynamics.
This communication claims the existence of a perpetuum mobile because surfaces with different curvatures have different vapour-pressures. According to the author, the liquid from the higher-vapour-pressure-surface-region consciously evaporates and condenses on the region of the lower-vapour-pressure-region.
This claim ignores the effects of gravity. In a gravitational field, the pressure of the vapour in the gas phase depends on the height. At higher elevations (at point A in the Figure), the pressure of the vapour is lower; simultaneously, the vapor-pressure of the concave liquid surface is also lower. While, at lower elevations (at point B in the Figure), the pressure of the vapour is higher; simultaneously, the vapor-pressure of the convex liquid surface is also higger. The liquid surface at any point is in equilibrium with the above vapour phase, and the vapour phase itself is in gravitational equilibrium. Hence, the dotted line transport process in the Figure does not exist.
The laws of thermodynamics are still valid.
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If you know any reference, please say me
Thank you so much dear Ming Xia
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Hello all dear
Question data:
Solvent enthalpy, amount of condensate in terms of time, temperature before and after solvent evaporation
you are welcome
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• η=η (T) =1-T1/T2 (excluding volume). E (V, T), P (V, T) contains volume, using η (T) Calculating E (V, T), P (V, T) does not match the experiment. This is in line with mathematical logic. The specific scientific calculations have changed their flavor. Please refer to the following figure for details
• η=η (T) =1-T1/T2 is about the ideal gas formula.
Now scientists have enough thermal property data to test the correctness of the second law of thermodynamics, as long as they are willing.
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Discontinuity (artificially) of The Thermophysical Properties of NIST affects the second law of thermodynamics：
1) Scientists create Type 2 perpetual motion machines;
2) Scientists have discovered new laws of phase transition.
3) Scientists don't need to create a bunch of fake things for the second law of thermodynamics.
The discontinuity (artificially induced) in the thermophysical properties of substances, such as temperature or pressure, can indeed affect the application of the second law of thermodynamics. The second law states that heat naturally flows from a higher-temperature region to a lower-temperature region, and this principle relies on the continuous and smooth behavior of thermophysical properties.
When discontinuities are introduced, it can lead to non-ideal behavior and deviations from the expected thermodynamic processes. For example, abrupt changes in temperature or pressure could result in unexpected phase transitions or heat transfer behaviors that don't follow the usual laws of thermodynamics.
Therefore, it's essential to maintain the continuity of thermophysical properties to accurately apply the second law of thermodynamics in various engineering and scientific applications. Researchers and engineers often work to minimize or correct such artificial discontinuities to ensure the reliability of thermodynamic calculations and processes
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Hello all dear
1. Ethylcyclopentane (C8H16): Ethylcyclopentane is a saturated hydrocarbon with a five-membered cyclopentane ring and an ethyl group (-C2H5) attached to one of the carbon atoms. It is a colorless, flammable liquid with a sweet odor. Ethylcyclopentane is commonly used as a solvent in various industrial processes due to its low toxicity and good solvency properties.
2. 2-Methylheptane (C8H18): 2-Methylheptane is another saturated hydrocarbon, also known as isoheptane. It has a seven-carbon chain with a methyl group (-CH3) attached to the second carbon atom. 2-Methylheptane is a clear, colorless liquid with a mild odor. It is often used as a solvent and can be a component in gasoline.
In your application, these two solvents are likely blended in specific ratios to create a mixture that can effectively dissolve and separate polymer pigments from recycled plastics and LDP (Low-Density Polyethylene). The choice of solvents may depend on their solvency properties, boiling points, and compatibility with the materials you are working with.
The process you described involves introducing this solvent mixture into a reactor at an elevated temperature (110°C). Due to the high temperature, some of the solvent evaporates, which can lead to a decrease in the reactor's temperature (to 98°C). This change in temperature is likely due to the endothermic nature of the solvent evaporation process, where heat is absorbed during vaporization.
The amount of condensate collected at different times provides valuable data for monitoring and controlling the process. It allows you to quantify the amount of solvent lost through evaporation and potentially recycle or replenish it as needed to maintain the desired solvent concentration in the reactor.
Overall, the formulation of your evaporated solvent involves blending Ethylcyclopentane and 2-Methylheptane to create a solvent mixture suitable for your polymer pigment separation and dissolution application. The process is carefully controlled to optimize solvent usage and separation efficiency.
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Hello all dear
The temperature of the vessel before being filled with solvent is 105 degrees, and after the solvent enters it, a certain amount evaporates and the temperature of the vessel decreases to 98.
Knowing the enthalpy of the solvent, how to calculate the volume of evaporated solvent?
Go for energy balance eqn. along with mass balance,
mH = m1H1+ m2H2 m = mass of entering stream
m1 = mass of evaporated stream
m2 = mass left in vessel
m = m1+m2
mH = m1H1 + (m-m1)H2 where H is Enthalpy for respective stream
after calculating mass you can convert its to volume by density or by using ideal gas equation for evaporated vapour.
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Presently computer science well applicable in various fields of science and many other fields. how best use in chemistry. .
Computer science has made significant contributions to the field of chemistry, enabling researchers to model complex molecular systems, predict chemical reactions, and analyze vast datasets. Here are some notable applications of computer science in chemistry:
1. **Monte-Carlo Simulations**: These are used in various areas, including environmental and chemistry fields. Monte-Carlo simulations can help in understanding complex chemical systems by using random variables and state-of-art techniques. [Link to the study](https://doi.org/10.54097/hset.v17i.2430)
2. **Molecular Docking and Dynamics**: Computational methods have been developed to solve the molecular docking problem, which is crucial for understanding molecular interactions and designing drugs. [Link to the study](https://doi.org/10.55522/jmpas.v12i1.4137)
3. **Material Science and Molecular Design**: The combination of material science and computer science has shifted the approach from "how to make a molecule" to "what molecule to make." This involves designing new ligands and complexing them with metals like Ruthenium to develop new materials with diverse applications. [Link to the study](https://doi.org/10.33696/pharmacol.4.042)
4. **Simulation of Practical Works of Crystallography**: Technological innovations have led to the development of computer applications that simulate chemical experiments, especially in the field of crystallography. This allows students and researchers to understand and study different crystalline structures using computer-based virtual experiments. [Link to the study](https://doi.org/10.35940/ijrte.c4665.098319)
5. **Computer-assisted Structure Elucidation (CASE)**: CASE systems have been developed to help in the structure elucidation of natural products using spectroscopic data. These systems mimic the expert's way of thinking during the process of structure elucidation. [Link to the study](https://doi.org/10.1039/9781849735186-00187)
6. **Visualization of Proteins**: Modern biochemists use computational methods to visualize proteins, find ligand binding sites, and understand the three-dimensional interactions with coordinated amino acid residues. [Link to the study](https://dblp.org/rec/journals/cse/PineP20)
7. **Nanoscience and Advanced Computational Methods**: Computational methods have been employed to study and design new compounds at the atomic level, leading to the development of software for targeted simulations. [Link to the study](https://doi.org/10.4018/978-1-4666-1607-3)
8. **Quantum Algorithms for Quantum Chemistry**: Quantum algorithms have been developed for ground-state, dynamics, and thermal-state simulation in quantum chemistry, providing a new dimension to the study of molecular systems. [Link to the study](https://arxiv.org/pdf/2001.03685)
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Combining the pictures to see the logical flaws and deviations from the experiment of the second law of thermodynamics.
1，Please take a look at the picture: Compared to the first law of thermodynamics, the second law of thermodynamics is a pseudoscience: Perpetual motion machine is a result and engineering concept, which cannot be used as the starting point of theory (the second law)
2，In the second picture, the second law of thermodynamics was misused by scientists, indicating that this theory does not match the experiment.
3，The above two explanations indicate that the second type of perpetual motion machine exists. If you're not satisfied, you can read my other discussions or articles.
4，With the second type of perpetual motion machine, the energy and environmental crisis has been lifted. By using the electricity generated by perpetual motion machines to desalinate seawater, the Sahara desert will become fertile land, and there will be no food crisis. War and Poverty Will Move Away from Humanity
You should ask scientists why they are not generous enough to use method a and instead use fraudulent method b
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These operations are catching up with the Korean superconductivity incident. The problem is very serious, and scientists are completely unaware.
Discontinuity (artificially) of The Thermophysical Properties of NIST affects the second law of thermodynamics：
1) Scientists create Type 2 perpetual motion machines;
2) Scientists have discovered new laws of phase transition.
3) Scientists don't need to create a bunch of fake things for the second law of thermodynamics.
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See picture for details
The second law of thermodynamics, no matter how powerful, must follow the laws of logic.
Discontinuity (artificially) of The Thermophysical Properties of NIST affects the second law of thermodynamics：
1) Scientists create Type 2 perpetual motion machines;
2) Scientists have discovered new laws of phase transition.
3) Scientists don't need to create a bunch of fake things for the second law of thermodynamics.
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What is the equation that describes the relationship between Gibbs elasticity and elastic modulus in polymers?
The relationship between Gibbs elasticity (also known as the Gibbs energy elasticity) and the elastic modulus in materials is described by the following equation:
E= ρ² / β x ∂ ² G / ∂ ρ²
Where:
- E is the elastic modulus (Young's modulus) of the material.
- ρis the strain (deformation) of the material.
- β is the volume strain, which is the change in volume divided by the initial volume.
- G is the Gibbs free energy of the material.
This equation relates the elastic modulus of a material to its Gibbs elasticity, which is a measure of the change in Gibbs free energy with respect to strain. The equation essentially quantifies how the free energy of a material changes as it is subjected to deformation or strain.
It's important to note that this equation is derived based on certain assumptions and approximations, and its applicability might vary depending on the specific properties of the material and the nature of the deformation. In some cases, different forms of this equation or other constitutive equations might be used to model the relationship between mechanical properties and thermodynamic quantities.
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This discussion addresses an important issue related to gases, which are known to be one of the fourth states of matter (gases, liquids, solids, and plasmas).
We learn from high school the ideal gas of equation of state, where particles are considered point particles, non-interacting, and massless (sometimes).
Even though using that simple model, many nontrivial questions that help to understand more complicated models can be answered for all Statistics, from the classical Gibbs and Maxwell Boltzmann distributions that obey Gaussian curves, where even degeneracy can be taken to be part of the exercise; to the more complicated Fermi-Dirac and Bose-Einstein statistics; where quantum effects are unavoidable, even if the gas is considered a free gas of electrons, or bosons non-interacting quasiparticles.
But what happens when the expansion terms are higher than for a simple gas and interactions are taken into account?
"What classical and/or effects survive from the ideal gas model and what has to be modified?" arises.
The question can be addressed for statistical equilibrium thermodynamics but also can be part of non-equilibrium statistical thermodynamics.
This science popularization thread will discuss some issues, as well as, some historical points in the development of this interesting subject, which belongs to exact and applied sciences as is the real gases issue.
Some new and old references cover some applied and theoretical aspects that will be addressed here. They are:
• "Statistical Thermodynamics: An Engineering Approach" by John W. Daily. Cambridge University Press, 2019.
• "Thermodynamics Statistical Physics and Kinetics" by Yuri Rumer, and M.S. Ryvkin. Central Books LTD, 1981.
Dear Prof. Ali Ghandili
Yes, the "real gases subject", & in general the subject of "dense gases, liquids and solids" is a wonderful subject, that with the development of fast speed computers, and new algorithms plus visualization tools is being explored intensively using different approaches, and where ab initio methods play a significant role.
Kind Regards.
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Generally, the rate of antioxidant reactions (activity) seem unrelated to total antioxidant effect (capacity); the latter is perhaps governed by thermodynamic considerations (pls. cf. redox reactions, Nernst equation etc.) and the complicated mess of real-world antioxidant reactions [1]. This is one justification cited for combining both rate and end-point measurements in order to get more representative antioxidant evaluations. Consistent with this approach, there is the general chemistry principle which states: the kinetics and thermodynamic properties of reaction are unrelated [2]. But why not? Some research (now quite old) shows that the rate of autoxidation reactions vary linearly as function of the net changes redox potential [ref. 3]. Marcus theory shows kinetic and thermodynamic "cross-overs" occur for single electron transfer reactions and (perhaps) other linear free energy relations [ref. 2]. Professor R.A. Marcus won the 1992 chemistry Nobel prize for the research completed initially in 1956; this model follows-on from Eyring's absolute reaction rate theory (cf. Activation free energy narrative) but in addition delta-G# is shown to be a function of Gibbs free energy (cf. delta-Go = n F Eo) plus a term for the solvent reorganization energy (L) – Marcus in brief!
Questions
Q1. Why is Marcus' theory not finding itself into standard chemistry texts?
Q2. Is there evidence for kinetics and thermodynamic cross-relations for single electron transfer reactions involving real-world antioxidants?.
Acknowledgement.
this discussion was prompted by this post on the Marcus theory.
References
[1]. Campos, A., Duran, N., Lopez-Alarcon, C., Lissi, E., 2012. Kinetic and stoichiometric evaluation of free radicals scavengers activities based on diphenyl-picryl hydroxyl (DPPH) consumption. Journal of the Chilean Chemical Society 57, 1381–1384. http://dx.doi.org/10.4067/S0717-97072012000400010
[2]. Silverstein, T.P., 2012. Marcus theory: thermodynamics CAN control the kinetics of electron transfer reactions. Journal of Chemical Education 89, 1159–1167.
[3]. Kurimura, Y., Ochiai, R., Matsuura, N., 1968. Oxygen oxidation of ferrous Ions induced by chelation. Bulletin of the Chemical Society of Japan 41, 2234–2239. https://doi.org/10.1246/bcsj.41.2234
Dear Richard K Owusu-Apenten , good question.
First: "the rate of antioxidant reactions (activity) seem unrelated to total antioxidant effect (capacity)."
When we saying antioxidant activity, we should clarify what Reactive Nitrogen or Oxygen Species (RNOS) is scavenged by antioxidant. The activity of a given antioxidant molecule is simply the rate constant of the reaction of this molecule with a given RNOS. You can apply whatever theory to link rate constants with thermodynamics. Commonly, this is the reaction of hydrogen atom abstraction, which belongs to the family of coupled electron and proton transfer. The Marcus theory is applicable for this type of reactions. For the mixture of antioxidants, the activity is the apparent reaction rate constant. The activity can be measured in units relative to an activity of a standard antioxidant such as ascorbic acid or Trolox.
Your Q1. Where is no "standard" chem text.
Q2. Tons of literature. This is the excellent book of the late Prof. Denisov
The total antioxidant effect (capacity) or TAC is the total number of radicals which can be scavenged by a single antioxidant or by the unknown mixture of antioxidants measured relatively to TAC of a standard antioxidant. TAC depends on assay (on RNOS used by an assay). There is no a single standard protocol to measure TAC. I believe, that the TAC based on ABTS radical is the mostly related to physiological conditions.
I discussed these question in my publications. I don't provide refs to avoid self advertisement.
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These two papers opposing the second law of thermodynamics received "recommendations" from 10 scholars. Welcome to read.
If you think it's good, give me a "recommendation" as well.
If you have two real gases, the claim dW=0 is incorrect, especially in the differential form, and therefore you will get additional terms in all subsequent equations.
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The original manuscript of this article is to answer some questions asked by Zhihu users, here added the second half of the content into the original manuscript, one for sharing, and the other to keep some views written casually, so as not to be lost, it may be useful in the future.
To talk about this problem under the topic of physics is because thermodynamics describes collective behavior and involves all levels. As far as the current situation of thermodynamics is concerned, classical thermodynamics + chemical thermodynamics seems more systematic, but it is not complete.
In comparison, thermodynamics is not as exquisite and rigorous as other theoretical systems of physics, the physical images of many concepts such as entropy, enthalpy and other thermodynamic potentials now are still unclear, and the mathematical transformations, from the perspective of physical meaning, cannot plainly shown what physical contents are transformed, the physical images of many derivatives, differentials, and equations are unclear, for instance, those derivatives, differentials cannot even distinguish between energy transfer and energy conversion.
The way classical thermodynamics is thought is also different from other systems of physics, the "subdivision" of the internal energy is not in place. We all know that the internal energy is the sum of different forms of energy within a given system, since there have different forms, then it should be classified, no, that's a pile. The description method is to see how much comes out through the heat transfer path, how much can come out through the work path, and calculate a total changes, the unique definitions are the parts that can be released in the form of work, called the thermodynamic potentials, when the path changed, one don't know whether they still are.
There is no even a basic classification of the internal energy, how to discuss the conversion between different forms of energy?
For example, a spontaneous chemical reaction, G decreases, S increases, but from the perspective of energy conversion, the answer by a professor of chemistry may not be as good as a liberal arts student who have studied a little in high school and forget most of it, the latter will most likely say that it is chemical energy converted into heat energy, although the terms are not professional, but the meaning of energy conversion is clear. The professors of chemistry know that G decreased, but they don't know what this decreased G turns into, there is no a complete narrative about energy conversion.
In the entire thermodynamic theoretical system, you can hardly find such a sensation, such as delicate, rigorous, physical image clarity, similar to that in the other theoretical systems of physics, and the appeasement philosophy is all over the place.
Statistical physics cannot independently establish equations for the relationships between thermodynamic state functions, relies on thermodynamics in the theoretical system, which also inherited the problems from thermodynamic theory. Statistical physics itself also brings more problems, for instance, statistical physics cannot explain such a process, an ideal gas does work to compress a spring, the internal energy of the ideal gas is converted into the elastic potential energy of the spring. If such simple, realistic problem cannot be explained, what are the use your statistical ensemble, phase spaces, the Poincaré recurrence theorem, mathematical transformations?
The thermodynamic direction maybe currently the last big chance in theoretical physics that can be verified or falsified, because it doesn't face the difficulties in other directions: you can write some dizzying mathematical equations, but maybe a century from now you don't know whether it's right or wrong.
Thermodynamics is the most grand theoretical system in the entire scientific system, a scientific system on natural evolution, although it is not yet complete, and has not yet risen to the level of fundamental theory, which provides a grand narrative of natural evolution, running through all levels.
Newton laws, Maxwell equations, Schrödinger equation, Hamiltonian dynamics, etc., for thermodynamics, that is only one law: the first law of thermodynamics, the law reveals the conservation of energy and conversion relationships of collective behavior at all levels and in all processes, the direction of change that the second law of thermodynamics described now has not been found in the dynamics of physics, will there be? there are some clues but not certain, because there is no corresponding theoretical framework.
The popular view of physicists on the conflict between time inversion symmetry of the fundamental process of dynamics and the second law is all wrong, the errors are: 1, confused the relationship between the fundamental laws, the theme that those dynamical equations discussed is the relation of conservation of energy, which correspond to the first law of thermodynamics, and the time inversion for the first law of thermodynamics is also symmetrical. 2, The symmetry of an equation and the symmetry of a phenomenon are two different concepts, the time inversion symmetry of the energy conservation equation only shows that energy conserve in past, present, and future, it does not explain whether the phenomenon itself is symmetrical in time inversion, the problem that the fundamental dynamic processes themselves are reversible or irreversible cannot be discussed by the equation of conservation of energy.
Have you noticed? in department of chemistry, one have to face the problem of time inversion asymmetry every day, and they also have dynamics, the chemical dynamics of time inversion asymmetry.
On the problem of irreversibility, those seemingly delicate, rigorous, time-inverse symmetrical physical systems are completely powerless, statistical physics is somewhat useful, such as explaining the diffusion phenomenon, calculating the number of collisions, its effective range has been limited by its theoretical postulates, the postulate of an equal probability determines that it is only valid for describing the processes tending to an equal probability distributions. In the framework of statistical physics, there is only one driving force of "change", tending to an equal probability distributions, the question is, the driving forces of "changes" in the real world around us are not only this one.
The second law of thermodynamics indicates that there are two different "dynamics": the physics of time inversion symmetry shows people a world without evolution, and the chemical dynamics of time inversion asymmetry shows us the different situations, whether the latter has universal sense at other levels is still unknown. From astrophysics to macroscopic, at least to the elementary particles level, all observed and confirmed results without exception strongly support the existence for the dynamics which are time inversion asymmetry, will it point to a final ending?
Let's take a look at the different thermodynamics?
The articles linked below show a new theoretical framework for thermodynamics that is different from what you can see in textbooks and other articles, and it also provides a new starting point for the study of a series of major problems.
Dear Tang Suye.
Perhaps you will find some answers to very important your questions in my report delivered in Novosibirsk last year.
It discusses the thermal expansion of the elements of the periodic table in the solid state.
The peculiarity of this report lies in the unusual concept that heat transfer in crystals is carried out by the action quanta (Planck's constant h), and not by the energy quanta. This is a very important point, since this quantum is a universal discrete element of any physical space. (This point is discussed in my other work .)
Another peculiarity that you can find in my report is that the thermal state of a crystal cannot be maintained and can not be described using phonons only, which are bosons. We need fermions. They are the excitations of electrons inside atoms. Here is the missing subsystem inside the crystal, which participates in the exchange of energy (quanta of action) with moving atoms in the crystal and thus maintains thermodynamic equilibrium as a whole. Obviously, the energy inside the atoms is a part of the internal energy of the entire crystal, as there are possible magnetic and spin excitations in it, which also exchange the energy and participate in maintaining equilibrium.
And in order not to get up (not to write) twice, I will say that the entropy S, in my view, is the logarithm of the sum of all possible distributions of M action quanta in the system over N of its elements.
Yours sincerely, Mikhail Dulin.
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You probably know that s=k*log(W) is carved on Boltzmann's tombstone. Did you know that he was never able to precisely describe W, at least not to the satisfaction of Albert Einstein, who chided him for not being able to do so? As for a breakthrough, I have always appreciated how Keenan, Keyes, Hill, and Moore (1969) demonstrated that all other thermodynamic properties can be derived through partial derivatives of the Helmholtz Free Energy. This fact was also utilized by Haar, Gallagher, and Kell (1984) plus a few more since then. I am also a big proponent of Maxwell's Criterion (see graph), which is misunderstood and even denied by some authors who are ignorant of its derivation.
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Double gas Thermodynamic cycle achieves 100% efficiency of heat engine Keywords: entropy, the second law of thermodynamics, free energy, Condensed matter physics, theoretical physics.
From a thermodynamics perspective, achieving 100% efficiency in a heat engine violates the second law of thermodynamics. This law essentially states that energy systems have inherent inefficiencies and that heat cannot be converted into work with 100% efficiency.
A heat engine operates between two thermal reservoirs at different temperatures (T_hot and T_cold). The maximum possible efficiency of such an engine is given by the Carnot cycle, which is an idealized thermodynamic cycle representing the maximum possible efficiency. The Carnot efficiency is given by:
Efficiency = 1 - (T_cold / T_hot)
where temperatures are measured on an absolute scale like Kelvin.
Some energy is always lost in any real process, often as waste heat. This is due to a property of the universe called entropy, which is a measure of disorder. The second law of thermodynamics can be expressed in terms of entropy by saying that the total entropy of a closed system will always increase over time.
The concept of a double gas thermodynamic cycle is interesting. No cycle, even if it's a double gas cycle or any other type, has been proven to achieve 100% efficiency. Any claim that a heat engine has 100% (or more) efficiency should be critically examined for errors, as it contradicts established physical principles.
While improvements can often be made to increase the efficiency of heat engines (such as by using better materials, reducing friction, or improving the design), the second law of thermodynamics fundamentally limits the maximum efficiency that can be achieved. Even under ideal conditions, some heat energy will always be lost and not converted into useful work.
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[[ lfh note: This question has been hijacked by mistakenly celebrating a very non-responsive lecture on turbulence with Popular Answers. The lecture is even placed before discussion of the question. In my opinion it was without malice by RG or the person who posted it. Please read that "answer" on Page 4 below after reading actual discussion and clarification of the question, because the lecture is good history. ]]
[Original question comment] I think that the process of flow curvature formation at any scale in a fluid requires a pressure gradient across the curvature. The result outside the curve is increased internal thermal energy there. During subsequent decay of the curved flow, the curving kinetic energy fills the low pressure inside the curvature.
You might find the thought experiment in my previous post interesting. It is a consequence of your suggestion that I read Sir James Jeans An Introduction to the Kinetic Theory of Gases and my choice to read his The Dynamical Theory of Gases as well. Writing the thought experiment triggered greater insight into processes because I had to address problems with answers that ring true. It also produced a richer view of a laminar flow past a cylinder with believable cause of curvature. I really appreciate our discussion that has led to it.
Happy Trails, Len
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Carnot efficiency=1-T1/T2<==>dE/dV=(dP/dT) * T-P. The accuracy of the second law of thermodynamics requires accurate E=E (V, T), P=P (V, T). Now, as long as you know that E is a function of volume, you can verify the correctness of the second law of thermodynamics.The second law of thermodynamics will be exposed to sunlight.
Dual gas Carnot cycle: heat is transferred from low temperature to high temperature without consuming external energy
Dual gas Thermodynamic cycle, where the adiabatic line intersects, violating the second law of thermodynamics
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I have come across this term several times. want to know the thermodynamic principle behind this. Can anyone suggest me suitable literatures in this regard?
I don't know. I'm in the process of writing a book, which puts me on a learning curve. I'll add it to my list of things-to-do.
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The second law of thermodynamics does not match the experiment, so scientists provide an explanation or make some adjustments. The maintenance cost of the second law of thermodynamics is really expensive. The first law of thermodynamics does not have such maintenance costs.
The second law of thermodynamics is not a fundamental science.
Here is a case study：In 1950, American scientists tested 10-30 times the prediction of the second law of thermodynamics.The change in capillary vapor pressure: The experiment is 10 to 30 times the second law of thermodynamics (Kelvin formula). Is the Second Law of Thermodynamics a pseudoscience?
Thermodynamics
Reading your question caused me to miss the article about vapour pressure in capillaries. The anomalous results contradict Kelvin's equation, not the Second Law. I will read the article carefully, but it looks as if the authors had a possible explanation in terms of long-range forces.
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For Methane dry reforming reaction (DRM), why do people try to avoid operating the reaction in thermodynamic equilibrium conversion?
Thank you!
Thermodynamic equilibrium includes reaction equilibrium, so no reaction.
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..
Ferry Melchels is correct about the thermodynamic reasons for poor co-solubility of polymers. Entropy fights your blending. Like dissolves in like, and gets fussier about match as MW goes up. However, quite a large number of miscible polymer pairs are known. Two common miscible blends are poly(styrene) (PS)–poly(phenylene oxide) (PPO); and poly(styrene-acrylonitrile) (SAN)–poly (methyl methacrylate) (PMMA). See for example,
I also see this 2014 article from Polymer Blends Handbook, which is paywalled, but the abstract says:
"Miscible polymer blends were once considered a rarity. However, extensive research has led to the discovery of a large number of miscible polymer blends. This Chapter is a compilation of miscible polymer blends reported in literature up to 2012." --
So yes, thermodynamics make miscibility more difficult as chain length increases, but not at all impossible.
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Question: The measured decomposition voltage of HBr is less than the reversible voltage, and the prediction of the second law of thermodynamics is exactly the opposite. Do you have any other examples that do not comply with the second law of thermodynamics (prompt: in Physical Chemistry)?
The following is the answer from ChatGPT:
I apologize for my previous response which might have been incorrect. The relationship between experimentally measured decomposition potential and reversible potential does not necessarily always conform simultaneously to the predictions of the Second Law of Thermodynamics, Faraday's laws and the Nernst equation. Thus, decomposition reactions with lower measured potentials do not necessarily indicate that some decomposition reactions do not conform to the Second Law of Thermodynamics.
In addition to the example of HBr, other anti-thermodynamic reversible reactions like the electrochemical deposition of thallium, where the reaction enthalpy is negative, also violate the prediction of the Second Law of Thermodynamics. Moreover, in cases involving biochemical reactions, some enzymes drive high entropy reactions (i.e. different types of molecules are combined to form larger, more complex molecules) by consuming energy molecules such as ATP, which is also an example of a violation of the Second Law of Thermodynamics.
However, it is important to note that these examples do not mean that the Second Law of Thermodynamics is incorrect, but rather that it is not applicable to all chemical reactions in the real world.
Carnot efficiency=1-T1/T2<==>dE/dV=(dP/dT) * T-P. The accuracy of the second law of thermodynamics requires accurate E=E (V, T), P=P (V, T). Now, as long as you know that E is a function of volume, you can verify the correctness of the second law of thermodynamics.
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By pushing the boundaries of conventional thermodynamic cycles, exploring new materials, and embracing sustainable technologies, I, as a researcher, can aim to enhance the efficiency of energy conversion processes beyond the limits imposed by the Carnot cycle. This research, coupled with my passion and dedication, has the potential to revolutionize energy utilization and make a significant impact on our quest for sustainable solutions. In this pursuit, I welcome and value all suggestions from fellow researchers as we collaborate toward advancing our understanding and unlocking new possibilities in this field.
Dual gas Carnot cycle: heat is transferred from low temperature to high temperature without consuming external energy
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for
Dear Víctor,
I hope you are fine.
Here are five questions related to thermometry and temperature metrology in the context of applied thermodynamics:
1. How can thermometry techniques be applied to accurately measure and monitor temperature profiles in a high-temperature industrial furnace?
2. What are the key considerations in selecting and calibrating temperature sensors for precise temperature measurement in a cryogenic storage system?
3. How can thermocouples and resistance temperature detectors (RTDs) be effectively utilized for temperature control in a chemical reactor?
4. What are the challenges and solutions in achieving accurate temperature measurements in extreme environments, such as aerospace applications or deep-sea exploration, using thermometry techniques?
and
5. How can the principles of temperature metrology be applied to ensure reliable and consistent temperature measurement in the pharmaceutical industry, particularly for the validation of temperature-sensitive drug storage and transportation?
Best regards,
Ciro
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The decomposition voltage is less than the reversible voltage. The second law of thermodynamics is wrong again.See screenshot for details
This is the content from university textbooks, and scientists have been humiliated by the Second Law of Thermodynamics.
Any tables are absolutely meaningless if they do not contain confidence intervals. Just as meaningless are any conclusions drawn from such tables.
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At which condition will the entropy of a pure solid be zero and what is the first law of thermodynamics according to Clausius?
Dr Rana Hamza Shakil thank you for your contribution to the discussion
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In what flow of energy is unidirectional fill in the blank and unidirectional flow of energy in an ecosystem is in keeping with the first law of thermodynamics?
Energy flow in an ecosystem is always unidirectional in nature because most of energy is released at the trophic level in the form of heat and performing metabolic activities. Hence 10% is transferred from one trophic level to another. This makes unidirectional flow of energy. The solar energy is captured by plants and it flows through different organisms of an ecosystem. All organisms are dependent for their food on producers, either directly or indirectly. This is a unidirectional flow of energy from the sun to producers and then to consumers. It supports the first law of thermodynamics.
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The change in capillary vapor pressure: The experiment is 10 to 30 times the second law of thermodynamics (Kelvin formula). Is the Second Law of Thermodynamics a pseudoscience?
All logically sound predictions of the 2LoT are correct, though some people may have made inferences that are lacking logical rigor and attribute them to the 2LoT. Such are failures of a particular person's logic, not a failure of the 2LoT. Simply saying that the 2LoT is more complicated than F=mA and thus potentially flawed is not sound reasoning. F=mA even when there is a seemingly chaotic explosion of particles and even when some of the mass is converted to energy. If a particular experiment doesn't show this, the experiment is flawed. We know this because every single time some diligent researcher has dug deep enough to verify these foundational principles, they have been confirmed--without exception. Another factor which may play into your example is the use of analytical derivatives, which presume an infinitely fine continuum, which is an approximation and not reality. Analytical calculus is not always accurate enough or entirely appropriate to handle every possible experiment. Again... when we can check it, the law holds, which should be adequate proof.
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Many researchers correlate their experimental data in an equation by various dimensionless parameters like Weber number, Bond number, Reynolds number, and so on for the thermal and hydraulic performance of a particular working fluid of heat exchanger. For the development of correlation of boiling and condensation heat transfer in a plate heat exchanger which are the most important dimensionless numbers?
How many data points are minimally required to develop a standard correlation?
I also find the use of Boiling number in the boiling heat transfer correlation and Bond number in the condensation heat transfer correlation along with Nusselt number, Reynolds number, and Prandtl number.
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Type 2 perpetual motion machines help humans achieve stellar civilization and eliminate it
Humans can only approach planetary level civilizations now. The following image shows the existence of type 2 perpetual motion machines, making travel and life within the solar system easier and safer.
The design of this perpetual motion machine has been recommended by two PhDs. If you support it, please provide a 'recommendation'.
What is the significance of the perpetual motion machine, the Russo Ukrainian War, and possibly the Third World War? Scientists should take on their own mission, and the key is that perpetual motion machines are indeed analyzable.
Dear Bo Miao.
You can write anything. Paper will endure everything.
The first law of thermodynamics dU = TdS - pdV is sufficient to understand temperature T as the rate of transfer (flow) of energy, and pressure p as the rate of transfer of momentum from one body in contact to another.
Therefore, you will never, under any circumstances, get a positive value if you subtract a large value from a small value.
Sincerely, Dulin Mikhail.
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As shown in Figure 1:
1. The second type of perpetual motion machine is derived from the first law of thermodynamics, which is the opposite of the second law of thermodynamics. From a theoretical and logical perspective, the two are contradictory.
2. The second law of thermodynamics mainly relies on empirical induction (position B in the figure):
2.1 Engineering experience: The perpetual motion machine has failed many times.
2.2. Dynamic experience: Elephants rush into porcelain shops; From life to death.
3. The correct method to oppose the second type of perpetual motion machine should be at position A in the figure, which is to prove through theoretical physics that the first law of thermodynamics cannot deduce the second type of perpetual motion machine.
4. Scientists have discovered a large number of cases: the second law of thermodynamics does not comply with experiments, as detailed in the link:
5. By constructing thermodynamic cycles, it is possible to transfer heat from a low-temperature heat source to a high-temperature heat source without consuming external energy. Please refer to the link for details:
This article collides mathematically with the second law of thermodynamics (expressed by Clausius). It's time to eliminate the second law of thermodynamics.
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I am trying to understand the difference between these potential energy and free energy landscapes like how these surfaces can be created and what kind of information can be drawn from these two landscapes.
A pedagogical explanation of the difference between a potential energy surface and a free energy surface is given in the Theory section of “Free Energy Surfaces for Liquid-Phase Reactions and Their Use to Study the Border Between Concerted and Nonconcerted α,β-Elimination Reactions of Esters and Thioesters,” Y. Kim, J. R. Mohrig, and D. G. Truhlar, Journal of the American Chemical Society 132, 11071-11082 (2010). doi.org/10.1021/ja101104q
Another pedagogical explanation of the difference is given on page 537 of “Chemical Kinetics and Mechanisms of Complex Systems: A Perspective on Recent Theoretical Advances,” S. J. Klippenstein, V. Pande, and D. G. Truhlar, Journal of the American Chemical Society 136, 528-546 (2014). doi.org/10.1021/ja408723a
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The phrase in the Title line imitates Karl Popper’s All Life is Problem Solving.
Since thermodynamics plays a role in life processes, it was surprising that searching “All life is thermodynamics” on Google on August 16, 2022 gave no results.
Don’t organisms seek to optimize and preserve the entropy of their internal energy distribution? And to optimize their use of energy and outcomes based on energy inputs? Aren’t survival and procreation ways of preserving previous products of energy use?
Is there justification for the statement, All life is thermodynamics? Or is the statement too simple to convey any insight?
Schrodinger in What is Life referred to thermodynamics, statistical mechanics; chapter 6 is Order, Disorder and Entropy. And more recently there is: J. Chem. Phys. 139, 121923 (2013); doi: 10.1063/1.4818538 Statistical physics of self-replication by Jeremy England.
Just one random emerent simulation that shows emerence of the second level emergence---emerents are brathing emerents---using modified 'Game of Life' cellular automaton, it was simulated by the open-source Python software GoL-N24.
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Under the conditions recognized by the second law of thermodynamics, the second type of perpetual motion machine can still be realized.
According to the second law of thermodynamics, if the Carnot efficiency of the working medium is "1-T1/T2", the second type of permanent machine cannot be realized. Therefore, it can be deduced that "dE/dV=(dP/dT) * T-P --- (1)"
Let's assume that
P=RT/V+a/V/V. da/dT=0; （2）
dE/dV=-a/V/V （3）
Meet (Formula 1), or (Carnot efficiency="1-T1/T2")
Substituting Equations (2) and (3) into the thermodynamic cycle in the following image, you will find that heat is transferred from low temperature to high temperature without consuming external energy.
Hello there,
Thank you for your message. I appreciate your interest in thermodynamics and the proposed system involving two gases and a Carnot cycle.
The Carnot cycle is indeed a fascinating theoretical model in thermodynamics, outlining the most efficient heat engine possible between two temperature reservoirs. As you mentioned, the second law of thermodynamics prevents the construction of a perpetual motion machine of the second kind that violates this principle.
Regarding the proposed system, I understand that it claims to achieve the free transfer of energy between high-temperature and low-temperature heat sources without consuming external energy. However, this claim contradicts the second law of thermodynamics.
While the equations you provided are interesting, unfortunately I suppose they are not sufficient to fully describe the system or to demonstrate the violation of the second law of thermodynamics. It is important to remember that the Carnot cycle is an idealization, and real-world systems will always have inefficiencies and losses that prevent them from achieving the claimed perpetual motion. Regards
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This thermodynamic cycle invalidates the second law of thermodynamics.
Science is expressed in mathematics. You can refine each formula. Then come to a conclusion.
In addition, the second law of thermodynamics does not conform to the experiment, see the link for details.
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Hello everyone!
I am working on CFD simulation of detonation of hydrogen and air. I am using a particular reaction mechanism for my simulation using Chemkin.
I searched for different thermodynamic data (.DAT files) in chemkin format needed to solve the reaction. I came across multiple thermodynamic (.DAT) files like GRI.dat, etc.
How to know which thermodynamic data to use for detonation? Is there any particular .dat file or thermodynamic data used for detonation?
I would appreciate the help.
A proplem which has arisen in thermochemical databases is that experimental and simulated data have been mixed, sometimes without proper declaration.
So, if you have conflicting data, you will be charged with the nasty task of tracing back how it has been determined. In case of doubt, you should rate experimental data over simulated data.
If you have conflicting experimental data, look at the original works, if available, and see if the measurement appears state of the art to you.
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vcb
The first law of thermodynamics, also known as the law of conservation of energy, states that energy cannot be created or destroyed, only transformed from one form to another. This law has many practical applications in our day to day life. Here are a few examples:
Home Heating: The first law of thermodynamics is fundamental in understanding how heating systems work in our homes. When we heat our homes, we are converting electrical or chemical energy into thermal energy. The heat energy is then transferred to our living spaces, which raises the temperature of the room. The law of conservation of energy tells us that the amount of heat energy supplied to the room must equal the amount of energy consumed by the heating system.
Food Digestion: The first law of thermodynamics also applies to our bodies when we consume food. Food contains potential energy in the form of calories. When we eat, our bodies convert the food energy into thermal energy, which we use to fuel our daily activities. This energy conversion process is what allows us to move and perform work.
Power Generation: Power plants, such as coal-fired power plants, generate electricity by converting the potential energy in fossil fuels into electrical energy. The first law of thermodynamics tells us that the amount of energy output from the power plant must equal the amount of energy input from the fuel source.
Transportation: The first law of thermodynamics is also important in transportation systems. When we drive a car, the chemical energy stored in the fuel is converted into kinetic energy, which propels the car forward. The energy transformation is subject to the first law of thermodynamics, which tells us that the amount of energy output from the engine must equal the amount of energy input from the fuel.
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So, the first law of thermodynamics has many practical applications in our day to day life, from home heating to transportation systems. It is a fundamental law of nature that governs how energy is transformed and used in our world ;)
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Hello,
Is there a way to calculate the Boltzmann weighted average of thermodynamic properties calculated using the hsa_gist command of the SSTMap tool?
thank you
The Boltzmann Weighted average for a thermodynamic property X is given by the following equation:
<X> = ∑X_i e^(-E_i/kT) / ∑e^(-E_i/kT)
where X_i is the value of the property for the i-th state, E_i is the energy of the i-th state, T is the temperature in Kelvin, k is the Boltzmann constant (1.38 x 10^-23 J/K), and the summation is over all states accessible to the system.
To calculate the Boltzmann Weighted average, you need to know the values of the property X and the energy E for each state. The Boltzmann factor, e^(-E_i/kT), describes the probability of the system being in the i-th state, based on the energy of the state and the temperature of the system. The Boltzmann factor assigns a weight to each state based on its energy and the temperature of the system, with lower energy states having a higher weight at lower temperatures.
To perform the calculation, you need to sum the product of X_i and e^(-E_i/kT) over all states, and then divide by the sum of e^(-E_i/kT) over all states. This gives you the Boltzmann Weighted average of the property X for the system.
Note that this calculation assumes that the system is in thermal equilibrium, meaning that the temperature is constant and the system has reached a state where the probabilities of each accessible state are fixed.
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10 consequences:
· Cryodynamics as a fundamental science was glimpsed by Zwicky in 1929
· Cryodynamics is the sister to Yakov Sinai’s deterministic Thermodynamics
· Cryodynamics confirms Zwicky’s global constancy of c from 1929
· Cryodynamics restores Saint Augustine’s eternal metabolizing cosmos
· Cryodynamics alters the properties of black holes
· Micro black holes are stable, uncharged and can eat earth inside out
· CERN’s official attempt to produce them is a risk to life for all
· A planet-wide IQ problem is in charge since 1929
· Stockholm loses ten Nobel medals
· The convictions even of large scientific groups can be marred
Oct. 12, 2020