{"id":741,"date":"2020-08-06T15:17:16","date_gmt":"2020-08-06T18:17:16","guid":{"rendered":"http:\/\/www.emsintese.com.br\/cursos\/?p=741"},"modified":"2020-08-06T15:17:18","modified_gmt":"2020-08-06T18:17:18","slug":"conceitos-sobre-entropia","status":"publish","type":"post","link":"http:\/\/www.emsintese.com.br\/cursos\/2020\/conceitos-sobre-entropia\/","title":{"rendered":"Conceitos sobre entropia"},"content":{"rendered":"\n
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Changes in the arrangement of ordinary objects do not change their entropy. Entropy depends on the dispersal of energy at a specific temperature, not on a pattern. (Information “entropy” with no inherent or integral energy factor therefore is only related in form, and not in function, to thermodynamic entropy that must have an enabling factor of energy. {por Frank Lambert}<\/em><\/p>\n\n\n\n

Tradu\u00e7\u00e3o: <\/em>Mudan\u00e7as na organiza\u00e7\u00e3o de objetos comuns<\/strong> n\u00e3o alteram sua entropia. A entropia depende da dispers\u00e3o de energia<\/strong> a uma temperatura espec\u00edfica, n\u00e3o de um padr\u00e3o. (A “entropia” de informa\u00e7\u00f5es sem fator de energia inerente ou integral, portanto, est\u00e1 relacionada apenas na forma e n\u00e3o na fun\u00e7\u00e3o \u00e0 entropia termodin\u00e2mica que deve ter um fator de energia capacitador. {Traduzido por Prof. Lu\u00eds Brudna}<\/p>\n\n\n\n

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“Entropy is disorder” is an archaic, misleading definition of entropy dating from the late 19th century before knowledge of molecular behavior, of quantum mechanics and molecular energy levels, or of the Third Law of thermodynamics. It seriously misleads beginning students, partly because “disorder” is a common word, partly because it has no scientific meaning in terms of energy or energy dispersal. {Por Frank Lambert}<\/em><\/p>\n\n\n\n

Tradu\u00e7\u00e3o: “Entropia \u00e9 desordem” \u00e9 uma defini\u00e7\u00e3o arcaica e enganosa de entropia que data do final do s\u00e9culo XIX antes do conhecimento do comportamento molecular, da mec\u00e2nica qu\u00e2ntica e dos n\u00edveis de energia molecular, ou da Terceira Lei da Termodin\u00e2mica. Isso engana seriamente os alunos iniciantes, em parte porque “desordem” \u00e9 uma palavra comum, em parte porque n\u00e3o tem significado cient\u00edfico em termos de energia ou dispers\u00e3o de energia. {Traduzidor por Prof. Lu\u00eds Brudna}<\/p>\n\n\n\n

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Energy disperses from being localized to becoming spread out if it is not hindered. This is the enabling factor \u00a0for all spontaneous physical and chemical events. Entropy change measures the dispersal of energy in a process: how\u00a0much\u00a0is spread out or how\u00a0widely\u00a0spread out that energy becomes. This is discussed in terms of macro thermodynamics, q(rev)\/T, and molecular thermodynamics,\u00a0kB<\/sub>\u00a0ln [microstatesfinal<\/sub>\u00a0\/ microstatesinitial<\/sub>\u00a0]. {Por Frank Lambert}<\/em><\/p>\n\n\n\n

Tradu\u00e7\u00e3o: A energia se dispersa de localizada para espalhada se n\u00e3o for impedida. Esse \u00e9 o fator que possibilita todos os eventos f\u00edsicos e qu\u00edmicos espont\u00e2neos. A mudan\u00e7a de entropia mede a dispers\u00e3o de energia<\/strong> em um processo: quanto \u00e9 espalhado ou qu\u00e3o amplamente dispersa essa energia se torna. Isso \u00e9 discutido em termos de macro termodin\u00e2mica, q(rev)\/T e termodin\u00e2mica molecular, kB ln [microestados final\/microestados final]. {Traduzido por Prof. Lu\u00eds Brudna}<\/p>\n\n\n\n

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Biochemistry students must use the concept of free energy change to understand reaction reversibility and the energetics of metabolism. The theory is founded on the Gibbs free energy function: \u0394G = \u0394H – T\u0394S. Reactant and product concentrations affect the \u0394S term and therefore determine whether \u0394G is positive or negative at a standard temperature. However, most biochemistry texts do little to connect the sign of \u0394G in this function to the concentration variables that determine it, and instead rely exclusively on the equation to relate these parameters. This can have the undesirable effect of rendering the Gibbs equation irrelevant for these students. For the biochemistry instructor, the challenge is to clarify the role of entropy in determining reaction directionality without digressing into aspects of thermodynamic theory that would be more appropriately covered in other courses. A model to explain the concentration dependence of the \u0394S term is presented in a format that is appropriate for an audience of biochemistry students, and the concepts are illustrated using an aqueous phase reaction, the anomeric conversion of glucose. {do site de Frank Lambert}<\/em><\/p>\n\n\n\n

Tradu\u00e7\u00e3o: Os estudantes de bioqu\u00edmica devem usar o conceito de mudan\u00e7a de energia livre para entender a reversibilidade da rea\u00e7\u00e3o e a energ\u00e9tica do metabolismo. A teoria baseia-se na fun\u00e7\u00e3o de energia livre de Gibbs: \u0394G = \u0394H – T\u0394S. As concentra\u00e7\u00f5es de reagente e produto afetam o termo \u0394S e, portanto, determinam se \u0394G \u00e9 positivo ou negativo a uma temperatura padr\u00e3o. No entanto, a maioria dos textos de bioqu\u00edmica faz pouco esfor\u00e7o para conectar o sinal de \u0394G nessa fun\u00e7\u00e3o \u00e0s vari\u00e1veis \u200b\u200bde concentra\u00e7\u00e3o que o determinam e, em vez disso, depende exclusivamente da equa\u00e7\u00e3o para relacionar esses par\u00e2metros. Isso pode ter o efeito indesej\u00e1vel de tornar a equa\u00e7\u00e3o de Gibbs irrelevante para esses alunos. Para o instrutor de bioqu\u00edmica, o desafio \u00e9 esclarecer o papel da entropia na determina\u00e7\u00e3o da direcionalidade da rea\u00e7\u00e3o sem se desviar para aspectos da teoria termodin\u00e2mica que seriam abordados de maneira mais apropriada em outros cursos. Um modelo para explicar a depend\u00eancia da concentra\u00e7\u00e3o do termo \u0394S \u00e9 apresentado em um formato apropriado para um p\u00fablico de estudantes de bioqu\u00edmica, e os conceitos s\u00e3o ilustrados usando uma rea\u00e7\u00e3o em fase aquosa, a convers\u00e3o anom\u00e9rica de glicose. {Traduzido por Prof. Lu\u00eds Brudna}<\/p>\n\n\n\n

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Changes in the arrangement of ordinary objects do not change their entropy. Entropy depends on the dispersal of energy at a specific temperature, not on a pattern. (Information “entropy” with no inherent or integral energy factor therefore is only related in form, and not in function, to thermodynamic entropy that must have an enabling factor of energy. {por Frank Lambert} Tradu\u00e7\u00e3o: Mudan\u00e7as na organiza\u00e7\u00e3o de objetos comuns n\u00e3o alteram sua entropia. A entropia depende da dispers\u00e3o de energia a uma temperatura espec\u00edfica, n\u00e3o de um padr\u00e3o. (A “entropia” de informa\u00e7\u00f5es sem fator de energia inerente ou integral, portanto, est\u00e1 relacionada <\/p>\n","protected":false},"author":1,"featured_media":743,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"class_list":["post-741","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-fq1","has_thumb"],"amp_enabled":true,"_links":{"self":[{"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/posts\/741","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/comments?post=741"}],"version-history":[{"count":2,"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/posts\/741\/revisions"}],"predecessor-version":[{"id":744,"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/posts\/741\/revisions\/744"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/media\/743"}],"wp:attachment":[{"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/media?parent=741"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/categories?post=741"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.emsintese.com.br\/cursos\/wp-json\/wp\/v2\/tags?post=741"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}