Energy levels

[parker]

I'm working on my background research for the "Rainbow fire" project, and I was reading all this stuff about electron's "energy levels." I don't quite understand that. Is it simply the distance from the nucleus that the electrons orbit? Please explain that to me.
Thanks for your time
--Parker Bradford

[kgudger]

Hi Parker - Welcome to the forum! I looked up the "Rainbow Fire" project, and found this information about energy levels:

"Physicists have found that the electrons traveling around the atomic nucleus can have only certain specified energy levels. In other words, the energy levels of atomic electrons are quantized. When provided with more energy, the electrons can move from one energy level to another, but these different energy levels are not continuous—they come in discrete steps."

To answer your question directly, the electron's energy level is not the distance from the nucleus. However, that model, called the "Bohr model", can provide relatively accurate results and is a useful introduction (see http://en.wikipedia.org/wiki/Bohr_model).

If you would like some more information or explanations, please post again! I hope this has helped.
Keith

[parker]

Thanks a bunch. That really helped my research. Is the electron hotter, faster in "orbit," or is it simply potential energy?
--Parker

[kgudger]

Hi Parker:

I'm not an expert on quantum mechanics, which describes "the energy of an electron depends not only on the intrinsic properties of its orbital, but also on its interactions with the other electrons" and "atomic orbitals are described as wave functions over space". Using the simpler Bohr model, I think you can think of the energy level as corresponding to the angular momentum (sort of like how fast it's moving). (I'd be happy if another expert chimed in here.)

Considering that an excited electron (moved up to another energy level) releases energy in the form of a photon, you could look at the energy level as "potential energy", too.

Keith

[parker]

OK! Thanks! That's great for my background research.
Like you said, if another expert has anything to add, I'd appreciate that too.

[geoffbruton]

Hi Parker!

I would preface my post by saying that this is not my area of expertise (so hopefully someone else will also be able to add more!), but I just wanted to add a few lines to Keith's comments. Is this the project that you're working on? https://www.sciencebuddies.org/science- ... o&from=TSW

As you have already found from the project background information, the energy of electrons within an atom are "quantized" and exist at discrete "levels". If energy is absorbed, the energy level increases by a specific amount - the electron now exists in a more excited state (since it has more energy). In order to return the atom to a more stable state, the electron must 'fall' to a lower (allowed) energy level. In doing so, energy is given out - as a 'package' of electromagnetic radiation, called a photon. (This form of 'light' is not necessarily visible light - but is visible in this experiment.) The amount of energy given out is always less than the amount of energy absorbed. A simple example of this is the use of a 'black light' - the 'light' given out is invisible to the naked eye (it is part of the ultra-violet region of electromagnetic radiation); however, some objects appear to glow when this light hits it. The higher energy of the UV light is being absorbed by the object - thereby giving it more energy. These excited electrons therefore move to a higher energy state. However, when they fall to a lower energy state, that absorbed energy must go somewhere - and so it is given out in the form of visible light (at a longer wavelength than the incident UV light). In fact, the object is fluorescing. Does that make sense? There is a whole field of spectroscopy built on this very idea!

There are several key words that should help you get started, but please don't worry if the material looks to be hard - quantum mechanics isn't easy! Basically, as long as you realize that energy is being absorbed (in one form, e.g. heat) and released (in one form, e.g. visible light), then that should help you understand the experiment.

I did some quick internet searching, and found a web-site that should get you started (but please do some more searching of your own!):

http://www.colorado.edu/physics/2000/qu ... index.html

Please let us know if you have any more questions, and good luck!
Geoff.

[parker]

Thanks Geoff! I checked out those websites; they're really cool!

[parker]

I've finished my background research successfully, but now I'm having trouble with the experiment. I'm haveing trouble dissolving large amounts of my solutes (Salt, damprid, et cetera) into the alcohol, and with the small amount I can get to dissolve, I'm getting the same orange flame as with the isopropyl alone. I even tried denatured alcohol, which burns blue, and I'm having the exact same problem. If anyone has a suggestion, I'd appreciate it.
Thanks!
Parker

[Gizzmo46]

Parker,
The first thing I would check is how much of the chemicals you are using. You should only be using a tablespoon of the isopropyl alcohol. Then you mix in a small amount of the solute. It only takes a little bit for one tablespoon of alcohol and it should mix in okay. The same color you are getting for everything might be due to contamination. As it only takes a very small amount of the solute, it is easy to contaminate your mixture. Make sure you wash everything thoroughly or use new pans and mixers for each mixture. This is very important when doing any kind of experiment with chemicals. Mixing the wrong things together in a lab setting can be disastrous! Try again and I'll keep thinking of what else might be going wrong. Good Luck!