So, in terms of finishing our Lewis structure, we're actually not done yet here, even though we have full octets, and we've used up all of our valence electrons, and the reason is because it's c n minus, so we need to make sure that that's reflected in our Lewis structure, so let's put it in brackets here, and put a minus 1.

那么，根据我们的路易斯结构的完成情况，我们实际上还没有全部完成，尽管我们有了填满的“八隅体“,而且用完了所有的价电子，原因就是因为这是一个负离子，我们需要确保我们的路易斯结构能反映出这一点，所以让我们给它加个括号，再加个负一。

麻省理工公开课 - 化学原理课程节选

N so, we've got five electrons here in the valence shell.

是1s2，2s2，2p3，Nitrogen，is，1s2，，2s2，，2p3，因此，有5个价层电子。

麻省理工公开课 - 固态化学导论课程节选

Core electrons are all those electrons held in really tight with the nucleus in the inner shells, whereas the valence electrons are only those electrons that are in the outer-most shell, or at your highest value of n of the principal quantum number.

芯电子是那些,在内壳层被原子核束缚得非常紧的电子，而价电子只包括,最外层的电子，或者说主量子数，n，的值最大的那些电子。

麻省理工公开课 - 化学原理课程节选