So what I want to point out with this case in beryllium is that you don't have to use all of the electrons to figure out the bond order, and in fact, once you get to molecules 10 that are from atoms with atomic numbers of 8 or 10, you're not going to want to maybe draw out the full molecular orbital diagram.

我要指出的是,在Be这种情况下,你不需要利用,所有的电子来指导键序，实际上，一旦分子中,原子序数到达了8或者，你也许不想画出,整个分子轨道图。

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