So when we deal with electrochemistry, we usually think of reactions in terms of half reactions.

所以当我们处理电化学时， 我们通常会根据半反应来考虑反应。

So batteries are designed to harness that energy by isolating the half reactions from each other.

因此， 电池旨在通过将半反应彼此隔离来利用这种能量。

The half reactions show more clearly what the electrons are doing.

半反应更清楚地显示了电子在做什么。

The voltage generated by many half reactions is already known and can be found in most textbooks or online.

许多半反应产生的电压是已知的， 可以在大多数教科书或网上找到。

If you were listening, you learned that electrochemical reactions are redox reactions that we describe in terms of half reactions.

如果你在听，你就会知道电化学反应是我们用半反应来描述的氧化还原反应。

And as I mentioned earlier, voltage is really just a way of expressing the electrical potential of each half reaction.

正如我之前提到的， 电压实际上只是一种表达每个半反应电位的方式。

Instead, as a general rule, when you convert a reduction half reaction to oxidation, the sign of the voltage is simply reversed.

相反，作为一般规则， 当您将还原半反应转化为氧化时，电压的符号会简单地反转。

And the electrical potential for the whole reaction, called the standard cell potential, is just the sum of the standard potentials of both half reactions.

整个反应的电势称为标准电池电势，只是两个半反应的标准电势之和。

Electrons can then cross from one half reaction to the other, only when we connect the cathode and the anode of the battery via conductors.

只有当我们通过导体连接电池的阴极和阳极时，电子才能从一个半反应交叉到另一个半反应。

When you break this down in to half reactions, first you have elemental zinc with an oxidation number of 0 being oxidized to zinc 2 ion.

当你将其分解为半个反应时，首先你会得到氧化值为 0 的元素锌被氧化为锌 2 离子。

To see how reduction potentials work in half reactions and combine in an overall reaction, let's consider a galvanic cell where zinc is oxidized and copper ions are reduced.

为了了解还原电位如何在半反应中起作用并在整个反应中结合，让我们考虑一个原电池， 其中锌被氧化而铜离子被还原。

When we balance the half reactions, we see that two electrons are released during the oxidation of each zinc atom, and one electron is consumed by each manganese 4 atom.

当我们平衡半反应时，我们看到每个锌原子在氧化过程中释放了两个电子，每个锰 4 原子消耗了一个电子。

Now if each of these half reactions occurred in contact with the other one, they'd just spontaneously go to equilibrium releasing energy as a bunch of heat which wouldn't be very helpful.

现在，如果这些半反应中的每一个都与另一个发生接触，它们就会自发地达到平衡， 释放出大量热量的能量， 这不会很有帮助。