Electrons are electrons. Why are some elements different?

Discussion in 'Physics' started by hp1729, Jan 13, 2016.

  1. hp1729

    Thread Starter Well-Known Member

    Nov 23, 2015
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    No, it's not a homework question.
    All atoms are made up of the same stuff. Electrons are electrons. So what makes some elements conductors and others not? Why do some elements form magnetic domains and become magnetized?
    The popular answer to the first question is that metals have one or two electrons in their valence shell and are easily pulled away to form an electrical current? Okay for the simple examples. but Lead has four valence electrons. So does carbon and silicon. Why so different electrically? Lead is a conductor. Carbon and silicon are semiconductors or insulators, depending on the crystal structure.
    Magnetism? Still really a mystery to me. Yes, I understand that when we get the electron shells to all spin in the same direction the magnetic fields join together. So why don't all elements behave the same way?
     
  2. crutschow

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    That's more of a quantum physics question then a general electronics question. :rolleyes:
     
  3. Picbuster

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    Please read the essays from Henry, Maxwell and Plancke on this subject.
     
  4. profbuxton

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    Why anything???
     
  5. hp1729

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    henry, Maxwell and Planck said a great deal of stuff. Can you provide some specific references?
    Maxwell, for instance, wrote more about observations on behavior of these things. Not so much on what was going on at the causal aspects of it all. Unless you have a reference????
     
    Last edited: Jan 13, 2016
  6. Papabravo

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    Interaction. Different elements behave differently because the geometric arrangement of quantum particles (electrons) allows or prohibits certain behaviors. There are several rules of quantum mechanics that you need to understand before you can put what we know about them into a coherent framework. Classical mechanics is just not up to the job, and no amount of hand waving can overcome the problem.

    Like many things in nature, there is an underlying differential equation that governs such behavior. It is called the Schrödinger equation, named for Erwin Schrödinger. It was developed in the early part of the 20th century. Here is the wiki:

    https://en.wikipedia.org/wiki/Schrödinger_equation
     
  7. hp1729

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    A good general statement for the test on Friday in a classroom. Specifics, please. Not equations but an explanation of what the equations mean.
     
  8. Papabravo

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    1. The equation is based on conservation of energy.
    2. The solutions require that some quantities are restricted to discrete values. Energy and angular momentum are quantized; position, momentum, and time are not.
    3. Values of position and momentum cannot be determined with arbitrary precision.
    4. Wave functions describe the probability of a behavior rater than the certainty.
     
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  9. AnalogKid

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    Richard Feynman was awarded the Nobel Prize in Physics in 1965 for his work in quantum electrodynamics. One of the science magazines said "He got the Nobel Prize for figuring out the electron." His lectures are available online.

    ak
     
  10. hp1729

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    That it may be. Should it go under the Physics forums?
     
  11. hp1729

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    Not that I claim an understanding of his work, but again, it looks like an observation of behaviors, not a cause of things or why of it all. He describes what the result is.
    Why are some atomic structures more magnetic than others?
     
  12. alfacliff

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    conductors have odd numbers of electrons in their outter shells.
     
  13. hp1729

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    ???
    Interesting. Where did you get that from?
     
  14. Papabravo

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    The Periodic Table of the Elements often contains the information about the distribution of electrons in each element, or you can google different elements to learn their structure.
    Here is copper:

    http://www.chemicalelements.com/elements/cu.html
     
  15. nsaspook

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    I know what you mean by 'why' but is that the correct question to ask?
     
  16. Papabravo

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    That some context is required for an explanation seems almost self-evident. Happens all the time when people ask questions, and are unprepared to understand the answers. It's not the fault of the answerer, it is the fault of the questioner.
     
  17. hp1729

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    What you say is true about copper and SOME metals. Some have two valence electrons, iron for instance. Lead is a good conductor with four valence electrons.
     
  18. Papabravo

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  19. BR-549

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    hp1729, What determines if a media is a conductor or not is..............the molecular structure obtained from the cooling, from a liquid state. Forming the solid structure, frees some electrons.

    This does leave a positive ion in the conductor, but as long as there is a free electron near by....the net charge is zero. That positive ion can not be neutralized with an inserted electron.....there is no physical space or room area for it. It will always be an ion. Until melting again.

    The free electrons collect on the surface, because they are self repulsive and the surface gives them the area of greatest separation. Not all of the electrons move with the same ease. Because of surface structure.

    The amount of free electrons available for flow is proportional to the voltage applied. As you increase voltage and thus current, a small number of free electrons will ionize bound valance electrons in the conductor. When that happens, another free electron will jump into that hole very quickly. When that happens, the captured electron will emit a deep red color that you can not see. But you can feel it as heat.

    As you increase current, the increasing number of valance expulsions, and of valance insertions, and of red emissions, and heat, will cause the conductor to glow red. Some conductors can glow white and not melt.

    If you dope a conductor with high valance impurities, you can set resistance per length, i.e. a resistor.

    The "magnetism" of a media depends on structure too. It's the alignment of the structure that determines an external magnetic field. The magnetic fields are always there, no matter what the media.
     
  20. hp1729

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    ???
    Are you talking about the whole block of material being neutral or are you talking about an individual atom at an instant? What is happening at the individual atom as one electron leaves at atom and it attracts another? The motion of the electron is current flow. The static condition of the atom is where voltage comes from. If we pull a bunch of electrons away from a chunk it develops a positive charge. Consider static charge, charging a capacitor or charging a rechargeable battery.
     
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