One of Nature's most basic rules:
Systems naturally seek their lowest available energy state - or - logs
- So, left alone, hydrogen atoms tend to be in the ground state.
Now, let's bombard an H atom with photons. What happens? Most
of the photons go zipping right past without interacting with the
H atom. But! photons with just the RIGHT energy get absorbed by the
Right means that the energy of the photon corresponds to the
energy level difference between ``allowed'' orbits in the H atom.
Absorbed means that the energy of the photon will now be gone
and the atom will be in a higher energy state.
- A photon with frequency will be absorbed
by an atom if the energy of the photon corresponds to an energy level difference
between allowed states in the atom
- What happens next? Remember, Nature seeks the lowest available energy level so
the bumped to an excited orbit will drop back to the ground state.
- Another Law of Nature, Conservation of Energy , states that the energy
difference between the excited state and ground state must appear somewhere when the
atom makes the transition. ``Somewhere'' is as a photon with the energy of the
- Below is a schematic diagram of the allowed orbits in a Hydrogen
atom. If you can answer the questions about it, you've got the idea.
- Which transition(s) correspond(s) to the absorption of a photon?
- Which transition corresponds to the highest energy photon emitted ?
- Which transition corresponds to the shortest wavelength photon emitted?
- Which transition corresponds to the higest frequency photon emitted?
Thu Jan 15 10:40:14 PST 1998