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Question about Hydrogen Spectrum (diagram with the lines) watch

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    How is the Hydrogen Spectrum (the diagram with horizontal lines) related to the appearance of spectral lines emitted from a hydrogen discharge? What determines the frequencies of the lines observed?
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    What level are you at?
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    well, i'll try to explain it in the simplest ways

    light behaves as both a wave and particles. particles of light are called photons. light also has different wavelengths an frequencies - giving different colours. Atoms can absorb these photons. So when an atom (in this case, hydrogen) absorbs these photons of light (energy), its electrons get excited. this means they jump up to another energy level (or sub-shell) and when the go back down to their normal level - they emit that energy back out (as photons) - giving off the coloured light they absorbed

    this gives you the absorption spectrum (black lines on coloured back ground) and the emission spectrum (coloured lines on black back ground) the lines are on the same place because the energy levels are the same
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    (Original post by z33)
    well, i'll try to explain it in the simplest ways

    light behaves as both a wave and particles. particles of light are called photons. light also has different wavelengths an frequencies - giving different colours. Atoms can absorb these photons. So when an atom (in this case, hydrogen) absorbs these photons of light (energy), its electrons get excited. this means they jump up to another energy level (or sub-shell) and when the go back down to their normal level - they emit that energy back out (as photons) - giving off the coloured light they absorbed

    this gives you the absorption spectrum (black lines on coloured back ground) and the emission spectrum (coloured lines on black back ground) the lines are on the same place because the energy levels are the same
    omg
    this is so well explained
    so the different lines represent the colours? - like shown in the picture attached
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    (Original post by Bloom77)
    omg
    this is so well explained
    so the different lines represent the colours? - like shown in the picture attached
    at uni
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    well the emission spectrum is meant to be coloured lines on a black background (remember black = absorbs) so if those lines were coloured and in the visible light spectrum yeah
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    (Original post by z33)
    well the emission spectrum is meant to be coloured lines on a black background (remember black = absorbs) so if those lines were coloured and in the visible light spectrum yeah
    Thank you!
    And so what's different between the balmer (visible light), paschen (IR), lyman (UV)
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    I understand that for balmer, electrons fall down to 2, and for lyman, electrons fall down to 1
    But why?





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    (Original post by Bloom77)
    Thank you!
    And so what's different between the balmer (visible light), paschen (IR), lyman (UV)
    Name:  ImageUploadedByStudent Room1475611272.024218.jpg
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    I understand that for balmer, electrons fall down to 2, and for lyman, electrons fall down to 1
    But why?





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    It's not a why question!

    Relaxation down to n=1 happens in the UV region of the spectrum while relaxation down to n=2 happens in the visible region.

    The why is because the energy released relaxing to n=1 is much greater than the energy released relaxing down to n=2,

    and E = hc/λ
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    (Original post by charco)
    It's not a why question!

    Relaxation down to n=1 happens in the UV region of the spectrum while relaxation down to n=2 happens in the visible region.

    The why is because the energy released relaxing to n=1 is much greater than the energy released relaxing down to n=2,

    and E = hc/λ
    If atoms absorbs the photons of light, they produce a Balmer series

    So if atoms absorb UV light, they produce the lyman series???



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    (Original post by Bloom77)
    If atoms absorbs the photons of light, they produce a Balmer series

    So if atoms absorb UV light, they produce the lyman series???



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    No, the different series refer to the emission spectrum.

    Electrons that have absorbed energy (and it could be from electricity or heat) relaxing down to lower levels and releasing quanta of energy.

    Lyman: n=n --> n=1
    Balmer: n=n --> n=2
    Paschen: n=n --> n=3
    Pfund: n=n --> n=4

    There are more, but you get the idea.
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    (Original post by charco)
    No, the different series refer to the emission spectrum.

    Electrons that have absorbed energy (and it could be from electricity or heat) relaxing down to lower levels and releasing quanta of energy.

    Lyman: n=n --> n=1
    Balmer: n=n --> n=2
    Paschen: n=n --> n=3
    Pfund: n=n --> n=4

    There are more, but you get the idea.
    Ohh so relaxing down to lower levels each time
    Like it'll go from a n=6 to a n=3 which would be paschen, then n=2, which would be balmer etc..


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    (Original post by Bloom77)
    Ohh so relaxing down to lower levels each time
    Like it'll go from a n=6 to a n=3 which would be paschen, then n=2, which would be balmer etc..


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    That's the ticket ...

    Check out the animation here
 
 
 
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