Difference between Lyman series and Paschen series
The origin of the spectral lines is comes from the Bohrs model. When electrons jump from higher energy states to lower energy state it release energy in the form of a photon. According to Bohr theory, the wavelengths of the hydrogen spectrum can be calculated by the Rydberg formula. The Lyman series, Paschen series are nothing but the different transition states for the hydrogen atom when an electron is excited. When electron is excited from one state to another state it will eventually lose energy. If electron is excited from n=1 state to n=3 state and return back by loosing energy to n=1 state then it is called lyman series. For lyman series it takes values from n = 2, 3, 4, 5……to n = 1. Similarly for paschen series when electron is excited from n=3 to n=5 then it will loose energy and return back to n=3 state then it is called paschen series. Paschen series takes values from from n = 4, 5, 6, 7……to n = 3. We can see these spectral lines spectrum by spectroscope. The difference between them is as follows.
Lyman Series |
Paschen series |
1) The spectral lines of lyman series is lie in the ultraviolet region.
2) The wavelength of lyman series is ranges from 900-1200 A°. 3) The wavelength of the first line of lyman series is 1215 A° 4) The wavelength of series limit of lyman series is 911 A° 5) For lyman series ni= 2,3,4… and nf = 1. |
1) The spectral lines of paschen series are lie in the infrared region.
2) The wavelength of the paschen series is ranges from 9500-18750 A°. 3) The wavelength of first line of paschen series is 18746 A°. 3) The wavelength of series limit of paschen series is 8201 A°. 4) For paschen series ni=4, 5,6… and nf= 3.
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