The emission lines from O III are called ____ because they are not visible laboratories on Earth due to the much greater pressure of the gas on Earth.
A) unique lines
B) unresolved lines
C) forbidden lines
D) unseen lines
E) "fathom" lines

Question

Quizplus · Accepted Answer

The emission lines from O III are called "forbidden lines" because they occur under conditions that are not typically reproducible in laboratories on Earth, such as the extremely low pressures found in outer space. These transitions are forbidden by selection rules in quantum mechanics under normal conditions, making them rare or impossible to observe on Earth where the gas pressure is much higher.

The Emission Lines from O III Are Called ____ Because