谢谢大家帮我翻译一下thermodynamically unfavorable re ...？ thermodynamically unfavorable reaction “热力学上不利的反应”严格意义上是“ 热力学 上难以自发(lack of spontaneity)进行的 吸能性 反应 “或者是δg为正值的反应，但不一定就是“热力学上 不能 自发进行的反应”。 因为也就像10楼指出的，有的反应在低温时候是不能自发进行的，但在高温就可能是会自发进行的了。即使在低温情况下，如果旁边还存在有其他的热力学上有利的反应，它也可以被另外这些热力学上有利的反应来带动而发生。所以 吸能性反应 是热力学上不利的，但它不是绝对“不能自发进行”的，也不一定非是难以发生的反应。 因为甲烷的键能很高，甲烷与二氧化碳的重整反应需要大量吸热，所以是 吸能性反应 ，故而叫做是热力学上不利的。 见 http:///thermodynamics.html 关于thermodynamically unfavorable reaction这方面的具体解释： in order to effectively evaluate the course (spontaneity or lack there of) of a reaction and taking into account both the first and second laws of thermodynamics, josiah gibbs defined the term, free energy which is defined as: δg = δh – tδs free energy is a valuable concept because it allows one to determine whether a reaction will proceed and allows one to calculate the equilibrium constant of the reaction which defines the extent to which a reaction can proceed. the discussion above indicated that a decrease in energy, a negative δh, and an increase in entropy, a positive δs, are indicative of favorable reactions. these terms would, therefore, make δg a negative value. reactions with negative δg values are termed exergonic and those with positive δg values endergonic . however, when a system is at equilibrium: δg = 0 gibbs' free energy calculations allows one to determine whether a given reaction will be thermodynamically favorable. the sign of δg states that a reaction as written or its reverse process is the favorable step. if δg is negative then the forward reaction is favored and visa versa for δg values that are calculated to be positive. 由δg = δh – tδs 的公式可以看出，有的反应在低温时候δg如果为正，在很高温下也可能会变成为负，反应就可以自发进行了。查看更多
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