No prefix: What is the energy required to ionize air?

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Discussion Overview

The discussion revolves around the energy required to ionize air, specifically focusing on the energy per mole needed to remove electrons from the constituent atoms of air. Participants also explore the implications of ionization, such as the recombination of charges and the time it takes for ionized air to return to a neutral state.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification, Homework-related

Main Points Raised

  • One participant inquires about the energy per mole required to ionize air and questions whether ionized air recombines and how long this process takes.
  • Another participant seeks clarification on whether the question pertains to the voltage required for air breakdown or the energy needed to remove a single electron from every atom in a mole of air.
  • A participant clarifies that they are interested in the energy required to remove a single electron from every atom in the mole of air.
  • One participant suggests that the question may be better suited for the Chemistry forum and discusses the need to break molecular bonds in nitrogen and oxygen before ionization can occur, providing a simplified assumption of air composition.
  • The same participant outlines a method for calculating the energy required by considering the bond energies of nitrogen and oxygen and the ionization energies of these elements.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the specific energy values or methods for calculation, and multiple viewpoints regarding the approach to the problem remain evident.

Contextual Notes

Participants reference various assumptions, such as the composition of air and the need to consider molecular bond energies, but do not resolve the mathematical steps involved in the calculations.

Who May Find This Useful

Individuals interested in the physical chemistry of gases, ionization processes, or those seeking to understand the energy dynamics involved in atmospheric chemistry may find this discussion relevant.

Alex Schaller
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Do you know which is the energy per mol required to ionize air? Once the air is ionized, does it recombine it´s charges so that after a while there is no ionized air at all? If this is the case, how long does it take for this to happen?
 
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Do you mean the VOLTAGE required for air break down? Or the energy required to remove a single electron from every atom in the mol?
 
I mean the energy required to remove a single electron from every atom in the mol.
 
I'm not sure whether or not this is homework, but this might be most appropriately answered in the Chemistry forum. Dredging up some of my high school chemistry, the process for ionization requires you to first break the molecular bonds (the triple bonds of nitrogen, and double bonds of oxygen) and form free atoms. Then, you need to ionize them.

Air is composed chiefly of nitrogen and oxygen (total 99%). I'd make a simplifying assumption and assume you have only nitrogen (79%) and oxygen (21%):
http://en.wikipedia.org/wiki/Earth's_atmosphere

Now, assume you have 1 mol of 'air' (0.79 mol of N2 and 0.21 mol of O2), figure out how much energy you need to break the bonds:
http://www.webelements.com/nitrogen/bond_enthalpies.html
http://www.webelements.com/oxygen/bond_enthalpies.html

Now figure out how much energy you need to ionize all these nitrogen and oxygen atoms (how many mols of each?)
http://en.wikipedia.org/wiki/Ionization_energies_of_the_elements

Presto! Amount of energy required to ionize air. Please show your work.
 
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