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AAS Spec. (1 Viewer)

jayy100

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Hey ok, so I basically get how AAS spec. works, but i want to know WHY it works.

I dont do physics, so could someone explain why the atomised particles from the flame absorb/respond to the light form the Cathode? Is it just because their both in the same 'emission spectrum' ?

And if so, does that mean that the monochromotor/photomultiplyer are just analysing how much unabsorbed light is reaching them?
 
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atoms consist of a nucleus (protons and neutrons) and outer shells of electrons

light is made up of massless particles called photons, these photons contain a discrete amount of energy depending on wavelength/frequency

the electrons in an atom occupy certain orbitals or 'energy levels' (i.e. 2, 8, 8, 18 etc.)

for an electron to jump to a higher orbital it needs a certain amount of energy

when light is shone on the atom, photons will strike the electrons and if that photon has enough energy then the electron will jump to a higher orbital

it will then quickly jump back to the lower orbital but in doing so it must release that same amount of energy (conservation of energy)

that energy is re-emitted as photons (i.e. light energy) but in all directions instead of the original single direction, scattering it, resulting in a deficiency of that particular wavelength of light

----

so the higher the concentration of a particular thing, there will be more electrons to absorb/re-emit and scatter light, resulting in less light going through

also, each element has distinct energy levels so testing can be done for a single element by choosing the correct wavelength of light
 

jayy100

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each element has distinct energy levels so testing can be done for a single element by choosing the correct wavelength of light
Can you explain this further? How does the monochromator choose or select the 'correct wavelength' ?
 

Equity

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atoms consist of a nucleus (protons and neutrons) and outer shells of electrons

light is made up of massless particles called photons, these photons contain a discrete amount of energy depending on wavelength/frequency

the electrons in an atom occupy certain orbitals or 'energy levels' (i.e. 2, 8, 8, 18 etc.)

for an electron to jump to a higher orbital it needs a certain amount of energy

when light is shone on the atom, photons will strike the electrons and if that photon has enough energy then the electron will jump to a higher orbital

it will then quickly jump back to the lower orbital but in doing so it must release that same amount of energy (conservation of energy)

that energy is re-emitted as photons (i.e. light energy) but in all directions instead of the original single direction, scattering it, resulting in a deficiency of that particular wavelength of light

----

so the higher the concentration of a particular thing, there will be more electrons to absorb/re-emit and scatter light, resulting in less light going through

also, each element has distinct energy levels so testing can be done for a single element by choosing the correct wavelength of light
dumb shit, go smoke some weed.
 
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Can you explain this further? How does the monochromator choose or select the 'correct wavelength' ?
e.g. an electron in a carbon atom requires a different amount of energy than a magnesium atom, every element/molecule is unique in this respect



these values are known beforehand

so when using AAS, say if the person wants to find out the concentration of calcium in a certain water sample, they'll choose the unique wavelength for detecting calcium
 

jayy100

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Alright thanks ohexploitable! You reallly conceptually understand your stuff!

And at "Equity", you're a loser. You're obviously depressed with some aspect of your life.
 
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Alright thanks ohexploitable! You reallly conceptually understand your stuff!

And at "Equity", you're a loser. You're obviously depressed with some aspect of your life.
"Equity" is matthew thomas goodwin, a 20 y/o who enjoys taunting hsc students

he's ugly and fat

i pity him sometimes
 

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