Name: John F.
Date: 2001 - 2002
Hello. I would like to know how fast an electron moves
when it changes transition states from ground state to a great distance,
then back to its ground state in its orbital. Does it move at the speed
of light or is the transition truly instantaneous? And if is
instantaneous, then how is this violation of the relativistic speed limit
accounted for? And if the transition takes a finite time, where is the
electron during its transition? Does it just disappear and reappear?
When an electron changes from its ground state to a higher-energy state, it
does not necessarily have to instantaneously change its position. Electron
orbitals are mathematically described as probability densities. All
orbitals (except for 1s) have specific two-dimensional regions of zero
probability (nodes), but otherwise the probability being at any distance
from the nucleus is finite. In other words, no matter what energy state an
electron is in, it's possible for it to be any distance from the nucleus.
When an electron changes its level, what changes is its energy (and possibly
things like angular momentum and spin as well). This affects its most
probable distance from the nucleus, but it does not specify a particular
separation between the nucleus and electron. So your question of how the
electron instantly changes its position is moot, because it does not
instantly change its position.
Richard E. Barrans Jr., Ph.D.
PG Research Foundation, Darien, Illinois
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