- #1
fog37
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Hello Forum,
I understand that an electron inside an atom/molecule has many possible transitions that it can make from a higher energy state (once it is excited there) to a lower energy state (possibly the ground state but not necessarily). For example, the electron can jump directly from ##E_{3}## to ##E_{1}## (ground level) or from ##E_{3}## to ##E_{2}## and then from ##E_{2}## to ##E_{1}##. There are selection rules that make some of those many transitions forbidden. However, many other transition possibilities remain for an electron. How does the electron decides which transition (among the allowed ones) it will make among the many possible? Is that a random, probabilistic choice? Two different atoms in the same sample, both in the same energy state, may choose different transition paths...
Fog37
I understand that an electron inside an atom/molecule has many possible transitions that it can make from a higher energy state (once it is excited there) to a lower energy state (possibly the ground state but not necessarily). For example, the electron can jump directly from ##E_{3}## to ##E_{1}## (ground level) or from ##E_{3}## to ##E_{2}## and then from ##E_{2}## to ##E_{1}##. There are selection rules that make some of those many transitions forbidden. However, many other transition possibilities remain for an electron. How does the electron decides which transition (among the allowed ones) it will make among the many possible? Is that a random, probabilistic choice? Two different atoms in the same sample, both in the same energy state, may choose different transition paths...
- When we look at a line spectrum of a gas like hydrogen or sodium atoms, there are multiple lines involved. Each line corresponds to a very specific electron transition. However, the various lines are NOT produced by the same atom. For instance, there are a large number of sodium atoms or helium atoms in the sample. These atoms, i.e. their electrons, were excited to various higher energy levels (not all the same level). The line spectrum shows the light emitted from all the different transitions that occurred in different atoms of the samples.
- I understand blackbody radiation which seems to depend only on the temperature of the sample (not its composition). I know that is an approximation. How does the blackbody radiation theory patch together with the theory of line spectra? Low density gases all have very unique line spectra (their signature). But if we looked at things from a temperature standpoint, the various low density gases should give off the same radiation if they had the same temperature. If we excite a gas with a discharge tube don't we also raise its temperature?
Fog37