So, we need to finish up with periodic trends.

那么，我们要先讲完周期性规律。

youdao

that's our topic here, we're talking about periodic trends.

这是我们的主题，我们要讨论周期性规律。

youdao

All right. So that is an anti-example of using periodic trends.

好的，这是一个关于使用元素周期律的反例。

youdao

We'll then take a turn to talking about the periodic table, we'll look at a bunch of periodic trends, including ionization energy, electron affinity, electronegativity and atomic radius.

然后我们再开始讲元素周期表，我们会看到很多周期性规律，比如电离能，电子亲和能，电负性以及原子半径。

麻省理工公开课 - 化学原理课程节选

It decreases. If you're still not completely up on the periodic trends, that is stuff that's going to be on the first exam, so make sure that you're able to do this without taking too much time to think about it.

它会降低，如果你还没有完全掌握周期性规律，而这是第一次考试要求的内容，因此请务必做到不用,想太久就能做到这点。

麻省理工公开课 - 化学原理课程节选

So, let's just take a quick example to show how not completely you can use these periodic trends, that there are limits.

那么，让我们举一个小例子来看一下,你是如何不能将元素周期律用在所有地方的，它是有局限性的。

麻省理工公开课 - 化学原理课程节选

One of the main ways the Project confronts these trends is to hold periodic conferences and seminars.

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