Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: Imo on April 20, 2012, 08:34:59 AM
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In the he hydrogen atom, how many emission lines would be observed considering only transitions between the four levels?
http://imageshack.us/photo/my-images/826/semttulohe.png/
I do not understand what the question wants...should the answer be 4? because 1 line of transition = 1 level = 1 emission line .
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There are only 4 spectral lines in the VISIBLE region.
See this : http://www.chemguide.co.uk/atoms/properties/hspectrum.html
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The Rydberg Eqn states:
1/λ = R[1/n1^2 - 1/n2^2]
Where λ is the wavelength of the light;
R is the Rydberg constant: R = 1.09737x 10^7 m^-1
n1 and n2 are integers such that n1 < n2
Consider n2 = 4; possible transitions are 4→3, 4→2, 4→1
Repeat logic for n2 = 3 and n2 =2.
Check ref 3; note only transitions to n1 = 2 are in the visible.
[1] http://en.wikipedia.org/wiki/Rydberg_formula
[2] http://en.wikipedia.org/wiki/Rydberg_constant
[3] http://en.wikipedia.org/wiki/Hydrogen_spectral_series
[4] http://www.chemguide.co.uk/atoms/properties/hspectrum.html