Can anything conduct electricity?

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In summary, materials have different levels of ionization potential, and it takes more energy to move electrons from a band with 13 electrons than it does for a band with 1 electron.
  • #1
Brown8633
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hi everyone.

i have always been taught that there are either insulators or conductors but can't everything conduct electricity with a high enough voltage? I know a free electron is needed to move from atom to atom to conduct electricity but if a high enough voltage is put through something does that not give a non-free electron enough energy to move to another atom?
 
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  • #2
Brown8633 said:
hi everyone.

i have always been taught that there are either insulators or conductors but can't everything conduct electricity with a high enough voltage? I know a free electron is needed to move from atom to atom to conduct electricity but if a high enough voltage is put through something does that not give a non-free electron enough energy to move to another atom?

Well materials have valance and conduction bands. The distance between the valance and conduction band is defined as band gap. As the band gap get bigger materials become more insulator because it gets harder for to excite an electron from the valence band into the conduction band. There is another term called Fermi level which determines behaivor of materials. Aplying a voltage only changes the Fermi level not the band gap.

So you can excite electrons from the valence band into the conduction band but at the end the conduction won't be the same as a metal. As well you might destroy materials.
 
  • #3
thanks for the reply.

so the valence bands are the lower bands of the atom that the electrons populate yeah? does this mean that the amount of valence bands change with which element it is? and is the conduction band the most outer band with the least amount of electrons on and the amount of energy to move an electron from the conductive band depends on how close it is to the nucleus for example in helium there is one shell of electrons so would it take more energy to move electron in helium than radon? also does it take more energy to move electrons from a conductive band with 13 electrons than it does for a band with 1 electron?
 
  • #4
Air is an electrical insulator. High voltage across an air gap does not conduct electricity until the electric field is sufficient to ionize the air and create free electrons. Here is a table of ionization potentials of the elements, including helium and radon:
http://environmentalchemistry.com/yogi/periodic/1stionization.html
Bob S
 
  • #5
On a related note:
I saw an MIT YouTube footage of a thick glass rod which, when heated by a blow torch would conduct electricity.
No practical purpose, I suppose, just a physics demo.

 
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  • #6
Please note that an electrical breakdown isn't typically considered as an electrical "conduction". So while it is true that if you apply a high enough field to almost anything, you can get charges to go across it, one typically don't consider this as an electrical conduction.

In fact, one could get charge flow at levels well below such breakdown via field emission/field current, i.e. tunneling process. This still isn't a "conduction" in the normal sense, it certainly has more controlled aspect of the phenomenon.

Zz.
 

Related to Can anything conduct electricity?

1. Can all materials conduct electricity?

No, not all materials have the ability to conduct electricity. Some materials, such as rubber and wood, are considered insulators and do not allow electricity to flow through them. On the other hand, materials like metals and water are good conductors of electricity.

2. What makes a material a good conductor of electricity?

The ability of a material to conduct electricity depends on the movement of electrons within the material. Materials with free electrons that are able to move easily are good conductors of electricity. This is why most metals, which have a high number of free electrons, are good conductors of electricity.

3. Can liquids and gases conduct electricity?

Yes, certain liquids and gases can conduct electricity. For example, water and other aqueous solutions have free ions that can carry electric current, making them good conductors. However, pure gases do not typically conduct electricity unless they are ionized or exposed to high temperatures.

4. Is there a difference between electrical and thermal conductivity?

Yes, there is a difference between electrical and thermal conductivity. Electrical conductivity is the ability of a material to conduct electricity, while thermal conductivity is the ability to conduct heat. Some materials may have high electrical conductivity but low thermal conductivity, and vice versa.

5. Can electricity pass through a vacuum?

No, electricity cannot pass through a vacuum. A vacuum is an environment with no particles, and electricity requires particles to flow through. This is why electrical insulators, such as air and glass, are used to separate conductors and prevent the flow of electricity in certain applications.

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