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Question about Hydrogen Spectrum (diagram with the lines)

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?
Reply 1
What level are you at?
Reply 2
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
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
at uni :smile:
Screen Shot 2016-10-04 at 20.36.05.png
Reply 4
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 :smile:
Screen Shot 2016-10-04 at 20.36.05.png


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
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)
ImageUploadedByStudent Room1475611272.024218.jpg

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)
ImageUploadedByStudent Room1475611272.024218.jpg

I understand that for balmer, electrons fall down to 2, and for lyman, electrons fall down to 1
But why?





Posted from TSR Mobile


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
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.
(edited 7 years ago)
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..


Posted from TSR Mobile


That's the ticket ... :smile:

Check out the animation here

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