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。

麻省理工公开课 - 化学原理课程节选

Now we're going to start in with that pi 2 p orbitals, which gives us 1 each, and then two each in those, we'll go up to our sigma 2 p z orbital.

现在我们要填π2p轨道，每个1个，然后每个2个，我们我们填sigma2pz轨道。

麻省理工公开课 - 化学原理课程节选

We'll start with Week 2 talking about Genetic Engineering; what's DNA, how can it be manipulated, how is our ability to manipulate DNA led to things like gene therapy which can now be done in people.

从第二周开始我们会讲基因工程,什么是DNA,怎么样才能操控它们,我们如何操作DNA,并将它应用于人类的基因疗法

耶鲁公开课 - 生物医学工程探索课程节选

So what we can say is look at each of these separately, so if we start with looking at the 2 p z orbital, the highest probability of finding an electron in the 2 p z orbital, is going to be along this z-axis.

我们可以来分别看看这些图，首先来看看2pz轨道，在2pz轨道里,找到电子的最大概率，是沿着ｚ轴。

麻省理工公开课 - 化学原理课程节选

So essentially, we have two ethene or ethylene molecules here to start with where these blue are our 2 s p 2 hybrid orbitals, so you can see that for each carbon atom, one is already used up binding to another carbon atom.

本质上，我们从两个乙烯分子开始,蓝色的是2sp2杂化轨道，你可以看到，对于每一个碳原子，其中一个已经用来和另外一个碳原子成键。

麻省理工公开课 - 化学原理课程节选

So I guess we'll start with helium 2.

我们从He2开始。

麻省理工公开课 - 化学原理课程节选

So this is our final equation, and this is actually called the Balmer series, which was named after Balmer, and this tells us the frequency of any of the lights where we start with an electron in some higher energy level and we drop down to an n final that's equal to 2.

把2代入到这里，所以得到1除以,这就是我们最终的方程，这叫做Balmer系，以Balmer名字命名的,它告诉我们从高能级掉到n等于2的,最终能级所发出光的频率。

麻省理工公开课 - 化学原理课程节选