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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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And in this case, the tie-breaker goes to the molecule in which the negative charge is on the most electronegative atom.
而在这种情况下，我们需要进行“附加赛“,也就是看看分子中带有负的,形式电荷的原子是不是电负性最高的。
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This is the fact that we occupy a finite volume in space, because they're little hard spheres in this molecule.
这是由气体分子在空间中,占据有限体积造成的,因为事实上它们是硬的小圆球。
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Now, chlorine I have to do a little bit more heavy lifting here because chlorine starts as a diatomic molecule.
现在，对于氯,我将会做更多的说明,因为氯元素起初存在于双原子分子中。
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There is still a tremendous amount of intellectual ferment and excitement in the capitals of Russia.
当时的知识分子还是相当活跃,特别是在俄国大城市中。
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What happens in the intestine is that food gets broken down into constituent molecules, some of those molecules are absorbed into our bodies.
在肠道中,食物必须分解成基本的组成分子,其中一些分子才能被我们的身体吸收
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You, the intelligentsia of the next generation, will be those that preserve this great treasure of Western culture and it is a great treasure of Western culture.
你们,未来一代的知识分子们,会成为这一西方文化中,灿烂瑰宝的保护者,它确实是西方文化中的灿烂瑰宝
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And because, of course, we have this carbon here what you end up doing is adding a carbon to your molecule.
因为，当然，我们这里有一个碳,接下来需要做的就是在你的分子中再加上一个碳。
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So, if we compare the sulfur to the oxygen, the oxygen it turns out is more electronegative and that is what holds the negative charge in this molecule.
因此，如果我们来比一下硫和氧，氧应该有更高的电负性,而在这个分子中它确实有负的电荷。
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So what that means is that's how much energy we would have to put into a hydrogen molecule in order to get it to split apart into its two atoms.
它的意义,就是我们需要向一个氢分子中注入这么大的能量,才能将它分解成两个独立的原子。
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That is going to equal the energy of the electrons in H2 minus the energies of the electrons in H.
这等于H2分子的能量2,减去H原子中电子的能量。
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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。
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Many neurotransmitters that carry signals between neurons in your brain work this way.
在脑部神经元细胞中,传递信号的神经递质分子的,作用原理就是如此
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So, for example, hydrogen or fluorine they'll never be in the middle, they'll always be on the end of a molecule.
比如，氢或者氟,永远不会在中间，它们总是会在分子中最边缘的位置。
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So in molecular orbital theory, what we did was we named orbitals based on their symmetry.
在分子轨道理论中，我们基于轨道的对称性给它们命名。
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now we're dealing with a lot of different atoms in the molecule, much more complicated than the initial case of the cyanide ion where we only had two.
现在我们要面对的分子中有很多不同的原子，比我们一开始只有两个,原子的氰离子复杂多了。
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And the last example that we're going to talk about is thionyl chloride, so it's s o c l 2. This is another good step forward, because now we actually have four different atoms in our molecule.
我们要讨论的最后一个例子,是氯化亚砜，就是硫，氧，氯，二，这又是一个进步，因为我们的分子中现在有四个不同的原子了。
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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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Any molecule can be an antigen; the food that you eat is full of antigens, microbes that try to live in your body are full of antigens.
任何分子都可以成为抗原,你吃的食物中富含抗原,试图栖息在你身体中的微生物充满抗原
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And there's disorder achieved by occupying the full available volume.
如果分子能够占据，所有可能的体积,那体系中就会有会无序。
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You do not get this line from molecular hydrogen.
从氢分子中我们得不到这种光线。
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And what you can see directly from looking at this energy level diagram, is that the molecule that we have is now more stable in the individual atoms.
你从直接看,能级图中会发现，分子比单个的,原子能量更低。
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So then in order to figure out the complete number of valence electrons in our molecule, we just add 5 plus 4 plus 1.
那么接下来为了得到,这个分子中价电子的总个数，我们只需要将五加上四，再加上一。
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So they like to be in the membrane and they're stable there and they won't come out because their structure allows them to exist in these unique spaces.
所以它们在膜里稳定存在,而且也不会脱离膜,因为这些蛋白质的结构使其能存在于,磷脂双分子层这个独特的环境中
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It's the way, for example, that foreign molecules or antigens get presented to cells of your immune system in order to start the process of making an immune response, so sometimes a cell/cell interaction.
通过这种方式,外源分子,或者说抗原,进入到免疫系统的细胞中后,就会开启免疫反应过程,有时候就是细胞之间的相互作用
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I mean, if the energy is lower to occupy a smaller volume, then if I have this room and a bunch of molecules of oxygen, and nitrogen and what have you in the air, and there are weak attractions between them, why don't they all just sort of glum together and find whatever volume they like.
我的意思是，如果占据小的体积会使能量降低，如果我有这样一个空间,和一些氧气，氮气和其他空气中有的气体，并且分子之间还有微弱的相互作用，为什么他们不黏在一起,然后占据他们所想要占据的体积。
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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。
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This is a picture of patch clamp, it's a device that engineers built to fasten onto individual cells in order to look at how molecules in the membrane of the cell are working, and I'll talk a little bit about that as we go along.
这是膜片钳的图片,工程师使用该装置固定单个细胞,由此观察,细胞膜中的分子怎样活动,在以后的课中我还会谈到这方面内容
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The cell that's producing the signal produces enough of the molecule so that it enters the bloodstream, it circulates throughout your body, eventually it reaches a cell at a great distance, which has a receptor for that ligand and the signal gets received.
发出信号的细胞产生信号分子,数量十分充足 能够进入到血液中,信号随着血液流遍全身,最终到达较远处的细胞,在这些细胞上有与配体配对的受体,信号被细胞接收
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When transcription happens and it turns out that there's a whole biology associated with this, including molecules that are floating around inside your cells called transcription factors, and their job-- they are molecules that are about particular genes and what some of the sequences and are able to turn on those genes inside cells, to make them transcribe.
研究证明,当细胞转录时,还有与之相关的一整套生物机制在运作,包括一种在你细胞中飘浮着的,称为转录因子的分子,它们的工作就是,它们知道该转录哪一段基因,该转录哪一段序列,然后把这些细胞中的基因激活,进行转录
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