If you click on Courseware you will get to this menu, the first of which preferences is Periodic Table.
如果你点击课件,就会来到这个菜单,第一个选择就是周期表。
Well, if we look on the chart, the first ionization energy is what is reported in your Periodic Table.
如果我们查阅图表,一级电离能,已经在元素周期表上标示了。
if we think about electronegativity as a periodic trend we can just draw our nice periodic table here, and let's separate it into quadrants.
如果我们来思考一下电负性的周期性规律,我们可以把我们漂亮的周期表画在这,然后把它分成四个象限。
So, remember when you're looking at your periodic table, don't forget about the lanthanides, sometimes they come into play.
因此,要记住,当你在看元素周期表时,不要忘了镧系元素,有时候也会用到它们。
And en route we discovered that we can divide the Periodic Table into metals, 75% which is about 75% of the Periodic Table.
我们发现,我们能够将元素周期表划出金属,大概占。
You are allowed to use on the test the official version of the Periodic Table of the Elements which most of you should have by now.
在测试中你们可以使用,化学元素周期表的官方版本,你们应该大部分都有了吧。
If you look on the Periodic Table this is 598 atomic hydrogen. And, sure enough, there is 13.598, which is this number here in electron volts.
如果你查找元素周期表上的氢原子,毫无疑问,它的电离能就是13。,这个数值也是电子伏的值。
So hopefully, it was a time issue in terms of looking at the periodic table, because let's have you tell me what are we looking for here?
希望刚才大家出问题的原因,是因为看周期表有时间限制,请大家告诉我,我们在这里找什么?
We can get this from the Periodic Table, so reported is Periodic Table.
我们能从元素周期表中得到这个,所以接下来要讲元素周期表。
It is just down the hall from this lecture theater. And you bring the Periodic Table and the Table of Constants and a calculator and something to write with.
就在这件教室下面的大厅那,你们带上元素周期表和常数表,还有一个计算器和一些写的东西。
So, if we look on the periodic table, comparing, for example, s to o, if we have s it's below o, what happens to ionization energy as we go down a table?
那么,如果我们看周期表上,比较,比如,硫和氧,硫在氧下面,当我们沿着表向下看的时候,电离能是怎么变化的?
And there's a lot we can explain by talking about what we see in the periodic table in terms of what different trends are in grouping different elements in different spots within the periodic table.
我们可以解释很多,通过讨论元素,周期表中的内容,按照各种不同的规律,将周期表中不同位置的元素分组归类。
So, this means we have the general trends down, so we should be able to look at actual atoms in our periodic table and graph them and see that they match up with our trends.
那么,这表示我们已经知道了大体的规律,现在我们可以来看看周期表中的,原子的实际情况,并把它们画出来,看看是否与我们的规律相符。
Depending on what kind of chemistry you go in to, you might accidentally memorize parts of the table, which is fine, but what you really want to know how to do is know how to use the periodic table.
取决于你今后从事哪个方向的化学研究,你可能会不经意地记住周期表的某一部分,这就够了,但是要注意,你真正需要知道的是如何使用元素周期表。
So as we go down we're now adding electrons to further and further away shells, so what we're going to see is that the atomic radius is going to increase as we're going down the periodic table.
当我们向下走时,我们会将电子加在越来越远的壳层上,因此我们将看到原子半径,将随我们沿周期表向下走而增大。
And this is the same periodic table that you're going to get in your exams, so it's good to practice doing your problem-sets with that periodic table so you're not relying on having the double check right there of seeing what the electron configuration is.
这也是你们考试时会用到的相同的表,这样你们就不会,所以使用周期表来做问题集,是很好的练习,这样你们就,不会依赖于再次确认,电子构型是什么了。
And what we've been talking about with all of these properties are, of course, how can we figure out what that is for a certain atom by looking at the periodic table, so we want to think about the periodic trend for atomic radius.
对于我们讲过的这些性质,我们所讨论的一直都是,当然是,我们如何能够判断某一个原子的这些性质,通过观察周期表,因此我们需要思考一下原子半径的周期性规律。
So, here we have a picture of Dmitri Mendeleev, who is one of the scientists responsible for first compiling the periodic table.
这是一张德米特里?门捷列夫的画像,他是最早制作,元素周期表的科学家之一。
See, if you know the Periodic Table then you know where elements are relative to one another.
如果你足够熟悉元素周期表,你可以知道,任何元素与另外元素的关系。
We need to add something else in order to explain what is going on in the Periodic Table.
我们需要引其他一些东西进来才能解释清楚,元素周期表中发生的这种现象。
So, then all we need to do to determine which elements that corresponds to is take a look at our periodic table.
因此,我们需要做的只剩下,在元素周期表中寻找,对应的元素有哪些。
So specifically, what we're asking here is as we go across the periodic table, we want to consider which has the smaller ionization energy.
具体地说,我们这里要问的是,从周期表来看,你认为,哪一个元素的电离能更低。
And since carbon's electronegativity is higher than that of hydrogen, which you would expect from where carbon lies on the Periodic Table. Think about it.
碳的高于氢的,你也可以从碳在,元素周期表上的位置,判断出来,试想一下。
So it turns out that we can really know a lot just by looking at the periodic table.
可见,我们只是看看元素周期表,就能知道很多信息。
So as we go across the row, and this is my beautiful picture of a periodic table here.
那么当我们沿着行向右走的时候,这是我漂亮的元素周期表。
And we know as we go across a row in the periodic table, what's happening is that z effective or the effective pull on the nucleus is increasing.
而我们知道沿着周期表的某一行向右看,有效核电量,或者说原子核的有效引力是在逐渐增大的。
Versus looking at, for example, helium or neon or argon, these are all inert gases, inert meaning essentially do not react, those were grouped together in the periodic table.
相反,他发现氦,氖,氩,都是惰性气体,惰性的意思是基本不参与化学反应,因此把它们放在周期表中的同一类里。
So similarly, as we now move up only one more atom in the table, 3 so to an atomic number of three or lithium, now we're going from six variables all the way to nine variables.
类似地就像我们现在,移动到周期表中仅仅多一个电子的情况,移动到一个原子数为,或者锂元素,现在我们从6个变量到了9个变量。
So let's turn our attention to a new topic, which is thinking a little bit about the periodic table, and also talking about periodic trends.
我们的新主题上,我们将会讨论一点关于元素周期表的知识,同时也会讲一讲周期性规律。
And after the periodic table was developed in the late 1800's, people didn't understand this quite as well, they took things a little more literally.
在十九世纪后期元素周期表经过发展之后,人们还没有很好地意识到这一点,他们的认识还有些粗浅。
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