Within the visible range of what we can see, you also want to know this relative order that's pretty easy -- most of us have memorized that in kindergarten, so that should be fine.

在可见光的范围内，你们要知道它们排列的,相对顺序，这非常简单,你们在幼儿园的时候。

麻省理工公开课 - 化学原理课程节选