In this model the arrangement of bonds around the central atom is considered to depend upon how many valence-shell electronpairs.
在这个模型中，认为围绕中心原子的化学键的排列取决于价层中电子对的数量。
2
If you took more advanced chemistry, you might have learned that bases are substances that can donate electronpairs, and that acids are substances that can accept them.
And because superconducting electronpairs only occur near the Fermi surface, in the vicinity of the images of Fermi surface, the study on this issue is very important.