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。
So we started with 10 valence electrons, we used up 8 of those electrons in terms of making bonds.
我们一开始有十个价电子,然后用掉了八个电子来成键。
Well, if this bond has completely identically equal sharing of electrons, then this bond will be nonpolar.
如果一根键连的两个原子,对键上的电子吸引程度是完全等价的,那么这根键是非极性的。
A TSV file, tab-separated values uses the same thing but a tab character, if you wanna output an actual tab character, the result of hitting the tab key, \t you do use backslash T. That's so those kinds of files are made.
而TSV文件,“制表符分隔“文件,顾名思义,就是用制表符来分隔每一列,如果你想输出一个真正的制表符,点击tab键,你也可以用,这就是那些文件的形成方式。
So we can have four total hydrogens bonding here, - and we can think about how to describe these carbon- carbon bonds.
我们这里一共有四个氢原子成键,我们可以考虑怎么来-,描述碳碳键。
So let's see, we started with 8 bonding electrons, and we used up only 4, so the answer is yes, we have 4 bonding electrons left.
那么让我们来看看,我们一开始有八个成键电子,然后只用掉了四个,因此答案应该是还有剩余,我们还剩下了四个成键电子。
We only have the one bond so the actual HF molecule is polar, it has a net dipole.
但HF中只有一根键,所以分子也是极性的而甲烷中有一个网状偶极。
The other thing is that we can re-write our h c n in terms of bonds.
还有一件事是我们可以用键的形式来表示氰化氢。
So if we go ahead and name this bond, what we're going to name it is sigma, - because that's the -- basically the shape of the bond or that's how our bond is coming together.
所以如果我们继续并且命名这一键,就是我们要命名的这个键,因为这是-,基本上键的形状,或者这就是键是怎么到一起的。
So let's think about methane using valence bond theory.
让我们用价电子成键理论来看一看甲烷。
so you can see that there is going to be two sets in antibonding, three sets in bonding for a net of one, giving us the single bond.
因此你能看到,反键轨道上有两组,三组成键,得到一组净成键,所以成的是单键。
And so both of these lobes together constitute a pi bond.
上下两片叶一起组成了一根π键。
And ultimately we are going to get to this state where we are going to form a bond.
最终我们将得到这个状态,即形成一根键。
I formed a bond, an ionic bond.
生成了一根键,离子键。
And, 435KJ/mol we can come up with a number of 435 kilojoules per mole HF Well, if we want to get HF, let's see what the FF bond is.
并且,我们想到一个数,如果我们想得到,我们看看FF键是什么。
However, on Friday we will use a different approach so we can talkabout bonding within atoms that have more than two atoms, molecules with more than two atoms.
但是,在周五我们,会用一种新的办法来讨论,不止两个原子的分子的成键。
So let's take the case of acetylene where we have two carbon atoms that are going to be triple bonded to each other, each are bonded to a carbon and then to one hydrogen.
让我们来看一看乙炔的例子,我们有两个碳原子,成三键,每个碳和一个碳一个氢相连。
And then we end up having 6 shared electrons, 2 from each of the bonds, so we end up with a formal charge on sulfur of plus 1.
然后我们有六个共用电子,每个键两个,因此最终硫的形式电荷量为正一。
So, another way to talk about dissociation energy is simply to call it bond strength, it's the same thing, they're equal to each other.
讨论离解能的另外一种方式,是直接称它为键的强度,它们是一样的,彼此相等。
So if you're trying to make a more complicated organic molecule carbon-carbon bonds are one of the most difficult things to make in organic chemistry, and it turns out that c n minus is a very reactive molecule, so it's a good way, even though we'll go over some drawbacks in a second, it is a good way to make carbon-carbon bonds.
如果你要合成一个更复杂的有机分子,碳碳键是有机化学中,最难制造的键之一,而实际上氰离子是一种具有很高活性的分子,用它是一个好办法,尽管我们一会儿将看到它的一些缺点,但它的确是一个制造碳碳键的好方法。
But since in drawing Lewis structures actually, in some cases you do, you can draw a dotted line that means a 1 and 1/2 bond, but most in most cases, we just draw out both resonance structures, and the way that we say it's a resonance structure is that we put it in the brackets and we put an arrow between it.
但是由于在画路易斯结构时,其实,在某些情况下是可以的,你可以画一条虚线来表示一又二分之一键,但是在多数情况下,我们就把两个结构都画出来,而我们说这是一个共振结构的表示的方法是,把它们放在括号里,并在中间放一个双箭头。
So that's two of our types of bonds in benzene, and we have one type left, that's going to actually be the double bond or the pi bond that So we can have one bond here between this carbon's p orbital and this carbon's p orbital.
这就是苯环里的两种键,我们还剩一种,那就是这些p轨道之间,形成的双键或者π键,我们可以在这个碳的p轨道,和这个碳的p轨道之间有个键。
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