"Suppose that, as indicated in the figure, the catalyst affects only the forward reaction. In its presence, the sum of the forward rates would clearly be larger than otherwise, while the backward rate would be unchanged. The position of equilibrium would therefore shift to the right, by the law of mass action. If we suppose further that the reaction produces heat q when it occurs, then a violation of the second law would be possible. We first allow equilibrium to be reached without the catalyst...and then add the catalyst, and heat δq is produced as the equilibrium is shifted. This heat is used to run a machine, and thus do work, cooling the system back to its original temperature in the process. We then remove the catalyst and the equilibrium shifts back. Heat δq is now extracted from the surroundings, which must warm the system back to the ambient temperature. A cycle has therefore been completed for which the net effect has been the isothermal conversion of heat energy into work, and a perpetual motion machine of the second kind has been found. We conclude that the supposed situation is impossible and that the catalyst must accelerate the forward and backward reactions equally." https://dtk.tankonyvtar.hu/bitstream/handle/123456789/8903/B9780120442621500128.pdf
The following conditional can be extracted from the above text:
If the second law of thermodynamics is true, catalysts accelerate the forward and backward reactions equally.
The consequent, "catalysts accelerate the forward and backward reactions equally", is false, and therefore the second law of thermodynamics is false as well (logic forbids the combination "true antecedent, false consequent"):
"However, many enzymes reversibly convert their substrate and product, and if one is interested in catalysis in only one direction, it may be necessary to prevent the reverse reaction...This is the first demonstration, on a specific example, that slowing a step that is rate limiting only when the enzyme works in one direction is a general mechanism for biasing the enzyme in the other direction." https://hal.science/hal-01977597/document
"PtO-clusters were found to have a pivotal role in unidirectional suppression of undesirable H2 oxidation [the backward reaction] in photocatalytic water cleavage process. More importantly, these PtO-clusters can also demonstrate excellent efficiency in hydrogen evolution rate [the forward reaction]." https://www.nature.com/articles/ncomms3500
"Interestingly, although [FeFe]-hydrogenases all possess the same active site H cluster, they display a large range of H2 gas oxidation and proton reduction activities, with some displaying a dramatic catalytic bias, that is, the propensity of a catalyst to effect rate of acceleration in one reaction direction over the other. " https://europepmc.org/article/pmc/pmc8653774
"The protein scaffold around an enzyme’s catalytic core exquisitely controls reactivity, including the direction and rate of chemical processes. Scientists refer to this fine tuning as “catalytic bias”—and how it occurs remains widely debated...A research team from three U.S. Department of Energy (DOE) national laboratories and four universities found that subtle changes to the environment surrounding some enzymes can not only change the rate of a cellular reaction by a staggering six orders of magnitude but also its direction. That reversal—the root of the catalytic bias dilemma—is like speeding in one direction at 10 miles-per-second, then going in the opposite direction at 1,000,000 miles-per-second." https://www.pnnl.gov/news-media/remarkable-rate-return-catalytic-bias
"Traditional catalysis is a central pivot around which much of the industrial and biological worlds turn. Positive catalysts satisfy three general principles. First, they increase reaction rates by providing lower activation energies for rate-limiting steps. Second, they are not consumed by their net reactions although they are intimately involved in them. Third, they do not alter final thermodynamic equilibria of their reactions. Epicatalysts bend this third principle in that they shift the final gas-phase equilibria of reactions." https://www.sciencedirect.com/science/article/pii/S2213138818301838
"In 2000, a simple, foundational thermodynamic paradox was proposed: a sealed blackbody cavity contains a diatomic gas and a radiometer whose apposing vane surfaces dissociate and recombine the gas to different degrees (A_2 ⇌ 2A). As a result of differing desorption rates for A and A_2 , there arise between the vane faces permanent pressure and temperature differences, either of which can be harnessed to perform work, in apparent conflict with the second law of thermodynamics. Here we report on the first experimental realization of this paradox, involving the dissociation of low-pressure hydrogen gas on high-temperature refractory metals (tungsten and rhenium) under blackbody cavity conditions. The results, corroborated by other laboratory studies and supported by theory, confirm the paradoxical temperature difference and point to physics beyond the traditional understanding of the second law." https://link.springer.com/article/10.1007/s10701-014-9781-5
The following conditional can be extracted from the above text:
If the second law of thermodynamics is true, catalysts accelerate the forward and backward reactions equally.
The consequent, "catalysts accelerate the forward and backward reactions equally", is false, and therefore the second law of thermodynamics is false as well (logic forbids the combination "true antecedent, false consequent"):
"However, many enzymes reversibly convert their substrate and product, and if one is interested in catalysis in only one direction, it may be necessary to prevent the reverse reaction...This is the first demonstration, on a specific example, that slowing a step that is rate limiting only when the enzyme works in one direction is a general mechanism for biasing the enzyme in the other direction." https://hal.science/hal-01977597/document
"PtO-clusters were found to have a pivotal role in unidirectional suppression of undesirable H2 oxidation [the backward reaction] in photocatalytic water cleavage process. More importantly, these PtO-clusters can also demonstrate excellent efficiency in hydrogen evolution rate [the forward reaction]." https://www.nature.com/articles/ncomms3500
"Interestingly, although [FeFe]-hydrogenases all possess the same active site H cluster, they display a large range of H2 gas oxidation and proton reduction activities, with some displaying a dramatic catalytic bias, that is, the propensity of a catalyst to effect rate of acceleration in one reaction direction over the other. " https://europepmc.org/article/pmc/pmc8653774
"The protein scaffold around an enzyme’s catalytic core exquisitely controls reactivity, including the direction and rate of chemical processes. Scientists refer to this fine tuning as “catalytic bias”—and how it occurs remains widely debated...A research team from three U.S. Department of Energy (DOE) national laboratories and four universities found that subtle changes to the environment surrounding some enzymes can not only change the rate of a cellular reaction by a staggering six orders of magnitude but also its direction. That reversal—the root of the catalytic bias dilemma—is like speeding in one direction at 10 miles-per-second, then going in the opposite direction at 1,000,000 miles-per-second." https://www.pnnl.gov/news-media/remarkable-rate-return-catalytic-bias
"Traditional catalysis is a central pivot around which much of the industrial and biological worlds turn. Positive catalysts satisfy three general principles. First, they increase reaction rates by providing lower activation energies for rate-limiting steps. Second, they are not consumed by their net reactions although they are intimately involved in them. Third, they do not alter final thermodynamic equilibria of their reactions. Epicatalysts bend this third principle in that they shift the final gas-phase equilibria of reactions." https://www.sciencedirect.com/science/article/pii/S2213138818301838
"In 2000, a simple, foundational thermodynamic paradox was proposed: a sealed blackbody cavity contains a diatomic gas and a radiometer whose apposing vane surfaces dissociate and recombine the gas to different degrees (A_2 ⇌ 2A). As a result of differing desorption rates for A and A_2 , there arise between the vane faces permanent pressure and temperature differences, either of which can be harnessed to perform work, in apparent conflict with the second law of thermodynamics. Here we report on the first experimental realization of this paradox, involving the dissociation of low-pressure hydrogen gas on high-temperature refractory metals (tungsten and rhenium) under blackbody cavity conditions. The results, corroborated by other laboratory studies and supported by theory, confirm the paradoxical temperature difference and point to physics beyond the traditional understanding of the second law." https://link.springer.com/article/10.1007/s10701-014-9781-5
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