Bilingual edition: English is preserved and Chinese follows each unit. Terminology uses the confirmed v20260916 glossary; automated semantic review remains traceable.
中英双语版：英文原文完整保留，中文紧随对应单元；术语采用 v20260916 确认表，自动语义审校结果可追溯。

Gibbs Free Energy and the Spontaneity of Chemical Reactions

吉布斯自由能与化学反应的自发性

The change in Gibbs free energy associated with a chemical reaction is a useful indicator of whether the reaction will proceed spontaneously. Since the change in free energy is equal to the maximum useful work which can be accomplished by the reaction

吉布斯自由能的变化是判断化学反应是否能自发进行的一个有用指标。由于自由能的变化等于反应所能完成的最大有用功

then a negative ΔG associated with a reaction indicates that it can happen spontaneously. This is consistent with the usual chemistry convention of treating work done by the system as negative work. Most common reactions can be assessed for spontaneity under standard conditions by looking up the associated thermodynamic quantities for each of the reactants and products. For non-standard conditions one can make use of the the expression for ΔG in terms of the other thermodynamic potentials

然后，与反应相关的负ΔG表明该反应可以自发进行。这与化学中将系统所做的功视为负功的惯例是一致的。大多数常见反应可以在标准条件下通过查找每个反应物和产物的关联热力学量来评估其自发性。对于非标准条件，可以利用ΔG与其他热力学势的表达式进行处理。

The change in free energy ΔG for a reaction can be expressed in terms of the equilibrium concentrations of the reactants and products. It is convenient to express ΔG for any reaction in terms of its value under standard conditions where values have been tabulated. For a reaction represented as

一个反应的自由能变化ΔG可以表示为反应物和产物的平衡浓度的函数。对于任何反应，用标准条件下的ΔG值来表示是方便的，这些值已经列在表中。对于一个表示为
A + B ↔ C + D

the change in free energy can be expressed as

自由能的变化可以表示为

Where ΔG0' is the standard free energy change and it is presumed that the temperature is 25°C = 298K.

其中ΔG⁰'是标准自由能变，并假定温度为25°C = 298K。
Example of hydrolysis of ATP
ATP水解的例子
 Index

Electrochemistry concepts

Reference
Ebbing
Ch 18

Karp
Ch 3
索引 电化学概念 参考 Ebbing 第18章 Karp 第3章
 
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Standard Free Energy Change

标准自由能变化

For biochemical reactions, it is convenient to reference the change in Gibbs free energy ΔG at some standard set of conditions. The conditions usually chosen are listed in the table. The standard value ΔG0' is determined from experimental data and allows the evaluation of ΔG for other experimental conditions.

对于生物化学反应，参考某些标准条件下的吉布斯自由能变化ΔG是方便的。通常选择的条件列在表中。标准值ΔG⁰'由实验数据确定，允许对其他实验条件下的ΔG进行评估。
Standard Conditions
  • T = 25°C = 298K
  • P = 1 atm
  • [C]=1 M, all reactants
    [C]=1 M，所有反应物
  • Water 55.6M
    水 55.6M
  • H+ conc = 10-7M (pH=7.0)
    H+浓度为10^-7 M（pH=7.0）
标准条件

The notation ΔG0' is used for pH=7.0 because ΔG0 is used for conditions pH = 0.0 or 1 M H+.

由于pH=7.0时使用ΔG 0'这一表示法，而pH=0.0或[H+]=1 M时使用ΔG 0。
Relation between ΔG0' and K'eq
ΔG 0' 与 K' eq 之间的关系
K'eq
K'eq
ΔG0'
kcal/mol
ΔG⁰' 千卡/摩尔
106
-8.2
104
-5.5
102
-2.7
101
-1.4
100
0.0
10-1
1.4
10-2
2.7
10-4
5.5
10-6
8.2
 Index

Electrochemistry concepts

Reference
Karp
Ch 3
索引 电化学概念 参考 Karp 第3章
 
HyperPhysics***** Electricity and Magnetism ***** Chemistry
HyperPhysics ***** 电磁学 ***** 化学
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