Pfund Series of spectral lines are produced forming the spectrum of hydrogen atom when electron jumps down to_________ orbit.
Correct answer: D. 5th
- A. 2nd
- B. 3rd
- C. 4th
- D. 5th
Explanation
The Pfund series is produced when electrons fall to the fifth orbit, n equal to 5, and lies in the far infrared. Lyman ends at n equal to 1, Balmer at 2, Paschen at 3 and Brackett at 4, a sequence worth memorising in order.
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About Spectrum of Hydrogen
The hydrogen spectrum consists of discrete emission lines produced when electrons fall between quantised energy levels and release photons. Questions use the Rydberg equation, photon energy and wavelength, and identify the Lyman, Balmer, Paschen, Brackett and Pfund series, which differ from continuous spectra.
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