📚 Quantitative Electrolysis | 定量电解
Quantitative electrolysis merges the principles of electrolytic cells with mole calculations, allowing you to predict exactly how much product forms at each electrode. By measuring current and time, you can calculate the charge passed and then use Faraday's laws to find the mass of metal deposited, the volume of gas evolved, or the mass of electrode dissolved. This topic is central to A-Level Chemistry and appears frequently in calculations and extended response questions.
定量电解将电解池原理与摩尔计算融为一体，使你能够精确预测每个电极上产物的生成量。通过测量电流和时间，你可以计算出通过的电量，然后利用法拉第定律求出沉积金属的质量、生成气体的体积或电极溶解的质量。这个主题是A-Level化学的核心，在计算题和长篇问答中频繁出现。
1. Introduction to Quantitative Electrolysis | 定量电解简介
In an electrolytic cell, an external power supply forces non-spontaneous redox reactions to occur. The amount of chemical change at each electrode is directly proportional to the total electric charge that passes through the cell. Quantitative electrolysis turns qualitative observations into precise numbers by linking charge (Q), current (I), time (t) and the Faraday constant (F) to the moles of electrons and, ultimately, to the moles and mass of products.
在电解池中，外部电源迫使非自发的氧化还原反应发生。每个电极上化学变化的量直接与通过电解池的总电荷量成正比。定量电解通过将电荷（Q）、电流（I）、时间（t）和法拉第常数（F）与电子摩尔数联系起来，并最终与产物的摩尔数和质量相关联，从而将定性观察转化为精确的数字。
2. Faraday's Laws of Electrolysis | 法拉第电解定律
Faraday's first law says that the mass of substance produced at an electrode is directly proportional to the quantity of electricity (charge) passed. Faraday's second law states that when the same quantity of electricity is passed through different electrolytes, the masses of substances liberated are proportional to their equivalent weights (molar mass divided by the number of electrons transferred per ion). These two laws form the theoretical foundation of all quantitative electrolysis calculations.
法拉第第一定律指出，电极上生成的物质质量与通过的电量（电荷）成正比。法拉第第二定律指出，当相同电量通过不同电解质时，释放出的物质质量与其化学当量（摩尔质量除以每个离子转移的电子数）成正比。这两条定律构成了所有定量电解计算的理论基础。
3. The Faraday Constant (F) | 法拉第常数 (F)
The Faraday constant is the magnitude of electric charge per mole of electrons. In A-Level calculations, it is usually taken as 96 500 C mol⁻¹ (often rounded from 96 485 C mol⁻¹). This constant is the bridge between the macroscopic quantity of charge and the amount of electrons measured in moles, allowing chemists to convert coulombs into countable particles that react in stoichiometric ratios.
法拉第常数是每摩尔电子所带电荷的数值。在A-Level计算中，通常取 96 500 C mol⁻¹（通常由 96 485 C mol⁻¹ 圆整）。该常数是宏观电荷量与以摩尔计量的电子数之间的桥梁，使化学家能够将库仑转换为参与计量比反应的可计数的粒子。
4. Relationship Between Charge, Current and Time | 电荷、电流与时间的关系
Electric charge (Q) is measured in coulombs (C) and can be found from the current (I) in amperes (A) and the time (t) for which it flows, provided time is expressed in seconds. The relationship is:
电荷（Q）以库仑（C）为单位，可根据电流（I，安培）和通电时间（t）求得，但时间必须以秒为单位。其关系为：
Q = I × t
For example, a steady current of 0.80
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