Let's look at the energetics of one of those electrons crashing into a hydrogen atom inside the gas tube.
我们一起来考察一下,其中的一个电子的能量,在阴极射线管中,撞击到氢原子上。
So what we end up with in terms of our bonding electrons is going to be 6 bonding electrons.
因此最终我们需要六个成键电子,那么我们可以来把它们填上。
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。
With one swipe, I can sign on electronic screen, get rid of paper completely.
刷一下,我就可以在电子屏幕上签字,完全丢掉纸质的收据。
You could come by during my office hours, which are on the syllabus, and you could send me e-mail and set up an appointment.
你们可以在我的办公时间来找我,教学大纲上有写我的办公时间,你们也可以通过电子邮件跟我预约
A point right on the screen mush like you might do when playing a video game.
屏幕上的一个点就像大家,在玩电子游戏时候见到的那样。
Now it's all electronic and it's done by the Internet, but it's the same thing.
现在一切都是电子化操作,通过互联网就可以实现,但本质上还是一样的。
It used to be that you had to big thick course packets that cost a lot of money, but now everything thankfully is available electronically on the course website.
过去你们总是,有厚厚的一打昂贵的资料,好在现在所资料都是电子版的,能在课程网站上得到
He was trying to describe electrons, but the theory said there are two roots in the quadratic equation and the second root is mathematically as interesting as the first one.
他当时只是想去描述电子,但是数学理论告诉我们,二次方程有两个根,而第二个根在数学上和第一个根一样有趣
So, step five tells us to add 2 electrons between each atom, so we add two there.
那么,第五步告诉我们在两个原子之间放上两个电子,因此我们在这放上两个。
So in order to fill them, he would have to have eight electrons or an octet around the cubes.
因此为了填满它们,他必须放上八个电子或者说一个“八隅体“,在立方体周围。
And this is just a Newtonian expression of momentum, the product of the mass of the electron times its instant velocity.
这只是牛顿学上关于动量的表达,用电子质量,乘以瞬时速度。
So we can write out what the electron configuration is here, and I think that I have already written that out for you in your notes.
我们可以在这里写出电子构型,我觉得我已经在你们,讲义上写出来了。
So, shared electrons are the ones that are shared between the carbon and the nitrogen, so we have 6 shared electrons, and we want to take 1/2 of that.
共用电子是那些在碳和氮之间,被它们共用的电子,那么我们有六个共用电子,然后我们要给它乘上二分之一。
As we increase the voltage, we get to a critical value at which it is possible to actually draw electrons across the gap.
当我们增加气压时,我们得到了一个临界值,在这个临界值上,将电子吸引过来是完全有可能的。
Here is the price-earnings ratio for the U.S. stock market from 1881 to the present-- this is also on that spreadsheet that you have on the website.
这是美国股票市场的市盈率,从1881年至今,这份数据也在网站上的电子数据表上
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。
What is the filling sequence of electrons in orbitals?
什么是电子在轨道上的排布顺序呢?
So what that means is that we're limited in any atom to having two electrons per orbital, right, because for any orbital we can either have a spin up electron, a spin down electron, or both.
这意味着在一个原子内,每个轨道上可以有两个电子,对吧,因为对任何轨道,我们可以有自旋向上或者自选向下或者两者都有。
Clearly, we put 2 for each bond, and now we end up having 2 remaining bonding electrons left.
显然,我们在每个键处放上两个电子,那么最后我们还剩下两个成键电子。
But can you see that the centers of electron deficiency lie on a sphere equidistant from the center?
但你看得到么,缺电子的地方分布在,与中心等距的一个球面上?
Because step five is that we need to fill in our bonding electrons, and we start it with filling in two electrons per bond.
因为第五步要做的是将我们的成键电子填在这,所以我们开始在每个键处填上两个电子。
Electrons will occupy orbitals in order of ascending energy, occupying the lowest energy first and up.
电子是按其能量递增顺序,排布在轨道上的,首先占满第一级,即最低能级。
For the sulfur, we start off with 6 valence electrons, minus 4 lone pair electrons, minus 2, taking in account our bonding electrons, so we end up with a formal charge of 0.
对于硫,我们从六个价电子开始,减去四个孤对电子,再减去二,算上我们的成键电子,因此最终我们有零个形式电荷。
So, which orbital would we take an electron out of if we were ionizing this atom here?
那么,如果我们要电离这个原子,应该拿走那个轨道上的电子?
Well, suppose I want to look at something like an electron in orbit here.
假如我想看到,轨道上像电子一样的东西。
And since we don't know the absolute up and down in the universe, it is possible that some of the electrons may be spinning up.
由于我们在宇宙里,并不知道什么是绝对的上和下,所以说上面的现象很有可能是,一些电子向上自旋引起的。
So, the wave function at all of these points in this plane is equal to zero, so therefore, also the wave function squared is going to be equal to zero.
因此这里的,波函数平方也等于零,如果我们说在这整个平面上,任何地方找到一个p电子的概率都是零。
Our step three is to figure out how many bonding electrons that we need, or excuse me, how many total electrons that we need to fill up our octets, so that's just going to be 4 times 8, which is 32.
我们的第三步是判断,我们需要多少个成键电子,不好意思,是我们总共需要多少个电子,才能填满所有“八隅体“,那么这就应该是四乘上八,也就是三十二。
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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