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In a metallic wire, what causes the free electrons to leave their shell? Watch

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    In a metal, I know you have the sea of delocalised electrons, where one (or a couple) of electrons are lost from the outer shell of each nucleus, what is the reason as to why the electrons come away from the nucleus and become free electrons?

    I know there is a weak force holding the outer layer of electrons to the actual electron shell, but why do some of those electrons escape the shell to become delocalised (free) electrons? What attracts them to leave the electron shell? And why do only some of those electrons in the outer shell escape, why don't all of the electrons in the outer shell escape?

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    (Original post by blobbybill)
    In a metal, I know you have the sea of delocalised electrons, where one (or a couple) of electrons are lost from the outer shell of each nucleus, what is the reason as to why the electrons come away from the nucleus and become free electrons?

    I know there is a weak force holding the outer layer of electrons to the actual electron shell, but why do some of those electrons escape the shell to become delocalised (free) electrons? What attracts them to leave the electron shell? And why do only some of those electrons in the outer shell escape, why don't all of the electrons in the outer shell escape?

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    By losing the electrons, the metal can attain a stable noble gas electronic configuration. They're not tightly bound, due to the electron shielding, so this makes it easy to lose the electrons (which is reflected in the ionisation energy) and become more stable.

    I'm pretty sure all electrons in the outermost shell escape. Aluminium for example, will form Al^{3+} and deposit three electrons into the sea of delocalised electrons
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    (Original post by h3rmit)
    By losing the electrons, the metal can attain a stable noble gas electronic configuration. They're not tightly bound, due to the electron shielding, so this makes it easy to lose the electrons (which is reflected in the ionisation energy) and become more stable.

    I'm pretty sure all electrons in the outermost shell escape. Aluminium for example, will form Al^{3+} and deposit three electrons into the sea of delocalised electrons
    All these examples I am seeing on youtube for Charge and drift velocity only talk about there being only one electron on the outermost shell layer. Is that the most common one to be dealing with? And if there were two, would both electrons be lost in the same way the single electron was lost when the shell only had one electron in the outer shell?

    I remember seeing that if there are like 6 electrons in an outer shell, then it will gain electrons instead of losing them. Why is this? Would it always gain enough to fill a whole shell? How can you tell if it will gain or lose electrons? Or am I overthinking this way too much? I see in the textbook it just says there are some free electrons, thats all the detail it gives.
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    (Original post by blobbybill)
    All these examples I am seeing on youtube for Charge and drift velocity only talk about there being only one electron on the outermost shell layer. Is that the most common one to be dealing with? And if there were two, would both electrons be lost in the same way the single electron was lost when the shell only had one electron in the outer shell?

    I remember seeing that if there are like 6 electrons in an outer shell, then it will gain electrons instead of losing them. Why is this? Would it always gain enough to fill a whole shell? How can you tell if it will gain or lose electrons? Or am I overthinking this way too much? I see in the textbook it just says there are some free electrons, thats all the detail it gives.
    If the metals are Group 1, they'll lose one electron. For Group 2, 2 and for group 3, 3. I'd say the most common ions are Cu+ and Cu2+, so expect one or two electrons lost probably.
    What do you mean regarding how the electrons are lost?

    It's simply easier to gain a stable noble gas electronic configuration by gaining electrons if you only need 3 or less electrons.
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    Band theory.
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    (Original post by h3rmit)
    If the metals are Group 1, they'll lose one electron. For Group 2, 2 and for group 3, 3. I'd say the most common ions are Cu+ and Cu2+, so expect one or two electrons lost probably.
    What do you mean regarding how the electrons are lost?

    It's simply easier to gain a stable noble gas electronic configuration by gaining electrons if you only need 3 or less electrons.
    Why does it want to have a full electron shell?
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    (Original post by blobbybill)
    Why does it want to have a full electron shell?
    Metals don't "want" anything. They are emotionless.

    Take sodium as an example. You've no doubt been taught that it "wants" to lose and e- to have an empty outermost shell.

    Actually, the removal of its outer e- is very endothermic, whereas the addition of an e- is actually exothermic. If sodium "wanted" to do anything, it would be to gain, not lose.

    As usual, in chemistry you get taught a series of rules which work at decreasingly basic levels.

    If you want to know about conductivity in metals based on e-, look up band theory. There is a reasonably simple HyperPhysics page which might get you started; this would be a good place to start: http://bfy.tw/9hkx
 
 
 
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