Question
Question: Smallest wavelength occurs for: A. Lyman series B. Balmer series C. Paschen series D. Bracke...
Smallest wavelength occurs for:
A. Lyman series
B. Balmer series
C. Paschen series
D. Brackett series
Solution
Bohr’s model of hydrogen atom defines the structure and spectrum of electrons present in the atom. According to him, an electron exhibits energy in the form of radiation when it moves from one transition state to another.
Complete step by step answer:
Bohr tells that the electron absorbs energy when it moves from its lowest stationary state to the higher transition state. Similarly it emitted energy in the form of radiation when moved from a higher transition state to the lowest stationary state. These radiations have a specific wavelength that resembles the wavelength of the electromagnetic spectrum.
There are different series present which correspond to different spectrum regions. These are:
series | n1 | n2 | Spectral regions |
---|---|---|---|
Lyman series | 1 | 2,3,4,……. | Ultraviolet |
Balmer series | 2 | 3,4,5,… | Visible |
Paschen series | 3 | 4,5,6,…. | Infrared |
Brackett series | 4 | 5,6,7,… | Infrared |
Pfund series | 5 | 6,7,8,… | Infrared |
The smallest wavelength is of the Lyman series that resembles UV spectral regions that ranges from 10-400nm.
**The correct option is A i.e. Lyman series.
Additional information:**
the observation of atomic spectra or line spectra of the hydrogen atom is carried out by the help of the spectroscopic method and the study of emission or absorption spectra is known as spectroscopy.
The wavelength of the series is calculated by the equation called as Rydberg equation given by the Swedish spectroscopic scientist Johannes Rydberg in which the value of R i.e. Rydberg constant is 109677cm−1
Note:
The spectrum is mainly prepared by Bohr for the hydrogen atom but later it was found that this can also be applied to the ions that have a single electron and is similar to that of a hydrogen atom. Some examples are He+,Li2+,Be3+and so on.