Ion Behavior in Electric Field

AI Thread Summary
When a gas is ionized in a strong electric field, positive ions drift towards one plate while electrons move to the other, leading to charge reduction unless a power source maintains current. The discussion explores methods to create ions and separate them from electrons without allowing neutralization, highlighting the challenges of using a positively charged plate for electron absorption. It raises questions about whether electric potential or sparks are responsible for ion creation, noting that while sparks are effective, field ionization can occur without them. The speaker expresses concerns about maintaining ion separation in a chamber without allowing sparks or neutralization, suggesting that traditional ion traps may not be suitable due to pressure limitations. Overall, the conversation focuses on the complexities of managing ion behavior in electric fields for specific applications.
Misha Kuznetsov
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If a gas is ionized using a sufficiently strong electric field (created by two plates, and where the gas is the medium in between), the positive ions would drift toward one plate while the electrons would be attracted to the other. What would happen when the electrons and ions reach the corresponding plates. Would the electrons be absorbed by the positive one and the ions neutralize at the negative one?

-Misha
 
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Yes.
This reduces the charge of the plates a bit, unless you have some power source connected (then you get a small current).
 
Okay. Is there a way to create the ions, and then to separate the electrons and ions by using an electric field, but without letting the ions neutralize?

Also, when a discharge occurs, is it the electric potential that creates ions or the actual spark?
 
You can have a hole in the cathode to allow some ions to shoot through. Will be tricky with vacuum and other issues. What do you want to do?

Misha Kuznetsov said:
Also, when a discharge occurs, is it the electric potential that creates ions or the actual spark?
You can have field ionization without sparks, but sparks are very effective at creating ions as well.
 
I want to make ions in a chamber. Then remove the electrons somehow, I was thinking that I could just have a positively charged plate to absorb them. The ions would repel one another and the pressure in the chamber would increase. So I don't think having a hole in the cathode would work very well for that.

The problem I'm having is that I can't let the ions neutralize, yet I can't use a barrier that would prevent a spark.
 
There are ion traps, but they work with magnetic fields and the pressure is tiny compared to atmospheric pressure.
 
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