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प्रश्न
Draw a neat, labelled energy level diagram for H atom showing the transitions. Explain the series of spectral lines for H atom, whose fixed inner orbit numbers are 3 and 4 respectively.
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उत्तर
Paschen series:
i. The spectral lines of this series correspond to the transition of an electron from some higher energy state to 3rd orbit.
ii. For paschen series, p = 3 and n = 4, 5,...
The wave numbers and the wavelengths of the spectral lines constituting the Paschen series are given by,
`barv=1/lambda=R(1/3^2-1/n^2)`
iii. Paschen series lies in the infrared region of the spectrum which is invisible and contains infinite number of lines.
iv. Wavelengths for n = 4 and 5 are 18750 Å and 12820 Å respectively.
Brackett series:
i. The spectral lines of this series corresponds to the transition of an electron from a higher energy state to the 4th orbit.
ii. For this series, p = 4 and n = 5, 6, 7,...
The wave numbers and the wavelengths of the spectral lines constituting the Brackett series are given by,
`barv=1/lambda=R(1/4^2-1/n^2)`
iii. This series lies in the ne ar infrared region of the spectrum and contains infinite number of lines. Wavelengths for n = 5 and 6, are 40518 Å and 26253 Å respectively
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संबंधित प्रश्न
Calculate the radius of second Bohr orbit in hydrogen atom from the given data.
Mass of electron = 9.1 x 10-31kg
Charge on the electron = 1.6 x 10-19 C
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Permittivity of free space = 8.85 x 10-12 C2/Nm2
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Calculate the energy required for the process
\[\ce{He^+_{(g)} -> He^{2+}_{(g)} + e^-}\]
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