So, our next level up that we can go is going to be the n equals 2 energy level, but we also have an l and an m value, 0 so our lowest l is going to be a there.

所以下一个能量,是n等于2的能级，但我们还有l和m的值，所以我们最低的l等于。

麻省理工公开课 - 化学原理课程节选