i know when a photon has the same energy as the difference in orbital energies the light will be absorbed, but what happens after that? how do you know if it will be emitted again or just turned into heat? details would be nice
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If light has been absorbed by raising the energy level of an electron within the atom then it hasn't contributed to the random kinetic energy of the atom so it hasn't raised its temperature.
The electron may, at any time, release the energy in steps. The size of the steps depends on the spacing of the energy levels themselves.
So what is possible depends on the specific atom involved.
To go further. Take an atom currently in ground state.
And imagine that 3eV would raise the atom to the third state. ( the second may be at 2eV)
Now the possibilities are a) release 3eV in one photon.
b) release 1eV in one photon and later release 2eV in another photon.
or of course, do nothing.
Whether any of these photons constitute heat is entirely dependent on what the energy levels are.
Always one possibility must be to reradiate the exact same energy of light that was absorbed in the first place.
The electron may, at any time, release the energy in steps. The size of the steps depends on the spacing of the energy levels themselves.
So what is possible depends on the specific atom involved.
To go further. Take an atom currently in ground state.
And imagine that 3eV would raise the atom to the third state. ( the second may be at 2eV)
Now the possibilities are a) release 3eV in one photon.
b) release 1eV in one photon and later release 2eV in another photon.
or of course, do nothing.
Whether any of these photons constitute heat is entirely dependent on what the energy levels are.
Always one possibility must be to reradiate the exact same energy of light that was absorbed in the first place.