ALL excited electrons give off energy when they return to their ground state from an excited state. Why don’t all heated substances give off colored light?
2007-11-08 16:10:20 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Physics
They do, but it's not always within the human visible spectrum. And it's not all from electrons dropping quantum states. That wouldn't explain black body radiation. The electromagnetic radiation has a broad peak which can be calculated from the temperature. See Planck's Law and Wien's Law in the reference.
2007-11-08 17:16:56 · answer #1 · answered by Frank N 7 · 0⤊ 0⤋
They do, in noble gases.
In these atoms, the energy levels are close to their ideal, "textbook" values, since the gases are not bonded to anything, and the electrons just jump up and down without interference from neighboring atoms.
In molecules, ionic solids, and metals, bonds cause the energy levels to change. This results in hybrid orbitals and other complications.
Since the electrons can now jump around from one energy level in one atom to another energy level in another atom, the energy difference, and hence their frequency, will become all confused. The substance will glow, but will give off a continuous spectrum, rather that a discrete line spectrum.
2007-11-08 16:59:56 · answer #2 · answered by Stephen S 3 · 0⤊ 0⤋