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    Question one: What would happen to the delocalised electrons if an electric current went through a metal?

    Question Two: What does the following experiment show/prove?

    Growing Silver Crystals
    By suspending a copper wire into a test tube of nitrate solution crystals of silver will appear on the copper wire after a few hours.

    Question Three: What is the purpose of galvanising steel? In my book it says 'galvinised steel is used to make channels for carrying insulated electric wires and many other containers and is not usually painted.'

    Thanks in advance.
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    1. Do you know what a current is?
    2 Where do you think the silver has come from?
    3. What is steel made from? What happens if you leave steel outside with no paint on?
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    (Original post by ThisIsOurDecision)
    1. Do you know what a current is?
    2 Where do you think the silver has come from?
    3. What is steel made from? What happens if you leave steel outside with no paint on?
    I'm still really stuck!
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    Ok, I'll give you a clue...current is the flow of charged particles (which could be ions, or...?)

    as for the second Q, where did the silver start, and where did it end up...

    Let's have some thinking...
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    Do the delocalised electrons spread the charge through the metal. Does the electric current mean that the metal has an overall positive charge because there are more positively charged ions than electrons. Or do the electrons become positively charged? Or is that not possible...

    The silver comes from the silver nitrate and galvanises the copper. This will prevent the copper from corroding.

    You cannot paint galvanised metals without preparing the surface because the protective layer prevents the paint from setting properly.
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    (Original post by Believeandsucceed)
    Do the delocalised electrons spread the charge through the metal. Does the electric current mean that the metal has an overall positive charge because there are more positively charged ions than electrons. Or do the electrons become positively charged? Or is that not possible...

    The silver comes from the silver nitrate and galvanises the copper. This will prevent the copper from corroding.

    You cannot paint galvanised metals without preparing the surface because the protective layer prevents the paint from setting properly.
    I'm surprised you have to answer these questions without having been taught the material first...before you get too confused, current in metals is simply the directional flow of electrons. Consider this - a metal wire conducts electricity without the metal actually moving. Solid metal is made up of atoms and as you know, these exist rather as cations in a 'sea of electrons'. Which one of the two phases do you think moves? Imagine a piece of metal being plugged into a circuit. What happens to its electrons?

    As for the second question, pay attention to what is happening at the ionic/atomic level. Are electrons being exchanged? Is so, how many and how do they change hands?
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    (Original post by =gabriel=)
    I'm surprised you have to answer these questions without having been taught the material first...before you get too confused, current in metals is simply the directional flow of electrons. Consider this - a metal wire conducts electricity without the metal actually moving. Solid metal is made up of atoms and as you know, these exist rather as cations in a 'sea of electrons'. Which one of the two phases do you think moves? Imagine a piece of metal being plugged into a circuit. What happens to its electrons?

    As for the second question, pay attention to what is happening at the ionic/atomic level. Are electrons being exchanged? Is so, how many and how do they change hands?
    The delocalised electrons will move as they are free to move not the atoms as the atoms are kept together due to the electrostatic forces caused between the electrons which are negatively charged and atoms which are postiively charged ions.

    After some contemplation I hope I have the right answer. The silver from the silver nitrate forms a ionic bond with the copper as silver needs to gain 3 electrons to stabilize its outer shell and copper needs to lose 3 electrons to become stabilized.
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    (Original post by Believeandsucceed)
    The delocalised electrons will move as they are free to move not the atoms as the atoms are kept together due to the electrostatic forces caused between the electrons which are negatively charged and atoms which are postiively charged ions.

    After some contemplation I hope I have the right answer. The silver from the silver nitrate forms a ionic bond with the copper as silver needs to gain 3 electrons to stabilize its outer shell and copper needs to lose 3 electrons to become stabilized.
    1) Yes the electrons will move, the electrons are in this case electricity carriers and there will be a potential difference between the two sides of the metal when a current goes through it, resulting from the unequal distribution of electrons. However, the stationary phase in this case are no longer the atoms (defined as neutral species) but metal cations. Be careful not to use the term atom for charged species.

    2) I'm afraid not, this is a simple redox reaction. All reactions are fundamentally the same - all that happens is that electrons go from a higher energy state to a lower energy state. In this case, Ag+ is reduced to metallic silver - Ag(0), which coats the copper. I believe this is called galvanisation of the copper but I guess galvanising could be even coating it with zinc or some other material. Anyway, the electrons required for the reduction of silver come from the copper wire so the 'bare' redox process is:

    2 Ag+ + Cu(0) -> 2 Ag(0) + Cu(2+)

    Nitrate ions are happy either way, copper suits them fine as a counterion. I'm not too familiar with the technology of galvanising steel and so on, but I'm pretty sure this is what happens in this case.
 
 
 
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