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He said that the percent ionic character, and this is within a bond, not for a compound, for a covalent bond.
他提到离子百分数，是指一根键中，并非一个分子中。
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CO Right, so you take the co here, and we take the valence here, and out of that comes covalent.
好了，然后我们看到，我们可以看到他的化合价，他们成共价键。
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A covalent bond is any time we have a pair of electrons that is shared between two different atoms.
所谓共价键就是我们有两个原子,共用一对电子。
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There's not actually chemical covalent bonds that are formed but it's a non-covalent interaction, usually dominated by hydrogen bonding.
所以配体和受体之间不生成共价键,这是一种非共价化合反应,它们通常以氢键相联
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OK, so what we've gone through today is we've introduced covalent bonding, and we've figured out a way to quantify it.
好的，那么我们已经经历了,是我们已经介绍了共价键，我们已经想出了一种定量的方法来。
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Likewise, the element that is a good electron acceptor in an electron transfer reaction is going to be the element that is going to hog the electrons in a covalent bond.
同样的，这个元素在一个电子转移反应中,是个很好的受赠者它将成为在共价电子,中吸引电子的元素。
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Not only did we figure out a way to describe how we quantify it, but we've also quantified how we tell the difference between covalent and ionic, and percent ionic character.
我们不仅想出了一个办法来描述,我们如何定量它，而且我们也定义,我们如何分辨共价性和离子性，以及离子百分数。
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And when we talk about covalent bonds, there's 2 properties that we'll mostly focus on, and that's going to be thinking about the bond strength or the energy by which it stabilized when it bonds.
而当我们讨论共价键的时候，有两点特性是我们最关注的，那就是键的强度,或者说成键之后能量降低了多少。
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So, we see is when we use the octet rule to look at fluorine molecule, we're combining two fluorine atoms, and what we end up with is an f f molecule where they're sharing two electrons, so making that covalent bond.
那么，我们看到把八隅体规则用到氟分子上,就是把两个氟原子组合起来，最终得到的氟分子中两个原子,共用一对电子，这就构成了共价键。
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He introduced the concept of electronegativity which was a measure, therefore, it is quantitative, of the atom's ability to attract electrons within a covalent bond and developed a scale of electronegativity.
他引入了电负性这一概念,一个反映着原子在成共价键时吸引电子的能力的数据标度，因此这是数量上的，在共价电子中,电子原子能吸引电子,并发展为一定规模的电负性。
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OK, he also, let me see, he also, lastly, to close us out, he also developed an analytical expression for the energy of that covalent bond, which is really what we want.
好的，他也，让我看看，他也，最终接近我们的，他也发明了一种分析方式,对于共价键能量来说，这是我们真正想要的。
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So specifically, today we're going to talk about covalent bonds.
特别地，今天我们要专门讲一讲共价键。
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Well, with covalent bonding, it's not so simple.
但对于共价键就没这么简单了。
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Now, usually this is a non-covalent interaction.
这通常是一种非共价化合反应
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So, somewhere in between, the bonds are, we have a range of bonds between ionic on the one hand, and perfectly covalent on the other hand.
因此在中间，这些键，一方面是离子性，另一方面是完美的共价键。
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The ability of an atom to attract electrons, and in particular, in a covalent bond.
原子对电子的吸引能力，特别是在共价键中。
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And so Pauling went further and said this is the purely covalent component.
然后鲍林更进一步,说这是一个完全的共价成分。
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And the key word for covalent bonds is the idea of being shared.
而关于共价键最关键的一点就在于共用的概念。
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This should make sense because if something has a low ionization energy, that means it's not very electronegative, which means it's going to be a lot happier giving up electron density, which is essentially what you're doing -- when you're forming covalent bonds is you're sharing some of your electron density.
这应该是合理的,因为如果某物的电离能很低，这也就意味着它的电负性也不高，那么它就会更愿意,放弃一定的电子密度，而本质上这正是你在,形成共价键时所需要做的,分享你的一些电子密度。
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They say homonuclear. So this is purely covalent.
而是用的同核，嗯，这是完全共价的。
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And he coined the term covalent bonding.
他创造了共价键这一概念。
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So, if we look at this graph where what we're charting is the internuclear distance, so the distance between these two hydrogen atoms, as a function of energy, -- what we are going to see is a curve that looks like this -- this is the general curve that you'll see for any covalent bond, and we'll explain where that comes from in a minute.
因此，如果我们来看一看这幅曲线图,这里我们画的横坐标是核间距，也就是这两个氢原子之间的距离，纵坐标是能量，我们看到的这是能量关于核间距的曲线-,这是一条普遍的曲线，在研究任何共价键时你都会遇到，我们马上就会解释一下它是怎么来的。
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We're going to talk about this kind of non-covalent interaction more when we talk about the immune system, because one example of ligand and receptors that's important in the immune system are antigens - foreign molecules, and antibodies - molecules that we produce.
当我们讲到免疫系统的时候,会更详细地谈到这种非共价化合反应,因为在免疫系统中,一个重要的配体受体结合反应,就是抗原,即外源分子,与抗体,这个人体自身产生的分子结合
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Well, if it is a good electron donor in an electron transfer reaction, if the same element finds itself in a covalent bond, it is going to be a good electron donor, although it is not full transfer.
如果它是一个在电子反应中,的好捐赠者，如果相同电子发现他在共价电子里，它将成为一个好的捐赠者，虽然没有完全转换。
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So as we said when we first introduced covalent bonds, it's a sharing of electrons, but it's not always an equal sharing.
当我们刚开始介绍共价键的时候，我们说过电子是被共用的，但是共用却不一定是均等的。
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So, that's basically the idea of how we are going to be thinking about covalent bonds.
那么，这就是我们所应该想到的基本思路,在考虑共价键时。
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So, in fact, yes, we did confirm that these covalent bond, at least in the case of hydrogen, we have confirmed by the numbers that we are at a lower energy state when we talk about the bonded atom versus the individual atom.
因此，事实上，是的，我们证实了共价键，至少在氢这种情况下，我们通过数据证实了,成键的原子处于能量更低的状态,当其与单个的原子相对比时。
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So, in talking about covalent bonds, we should be able to still apply a more general definition of a chemical bond, which should tell us that the h 2 molecule is going to be lower in energy than if we looked at 2 separate hydrogen atom molecules.
那么，既然提到了共价键，我们应该还可以,给化学键下一个更普遍的定义,那就是告诉我们氢分子能量应该更低,与两个分开的氢的单原子分子相比。
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That is what gets crunched down to covalent bonding.
这就要归结与共价键。
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This is purely covalent because all it is is homonuclear bond energies.
是一个完全的共价成分,他的理由是他们都是同核共价。
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