Hydrogen Spectrum refers to the collection of characteristic frequencies or wavelengths of lights emitted by hydrogen atom when excited electrons returns to the ground state from higher energy state.
The “Hydrogen spectrum” is composed of several series of spectral lines, each corresponding to a different set of electron transitions.
The most well-known series in the spectrum are the Lyman, Balmer, Paschen, Brackett, and Pfund series.
How Hydrogen Spectrum is created ?
The hydrogen spectrum is generated through the interaction of hydrogen atoms with electromagnetic radiation.
When hydrogen atoms are excited or energized, their electrons can undergo transitions between different energy levels.
These transitions result in the emission or absorption of photons, which are packets of electromagnetic radiation.
- Excitation:
Hydrogen atoms can be excited by various means, such as thermal energy, electrical discharge, or exposure to a high-energy source like a flame or an electric discharge.
The excitation causes the electrons in the hydrogen atoms to move from their ground state (lowest energy level) to higher energy levels. - Electron Transitions:
The excited electrons in hydrogen atoms are not stable in their higher energy levels and tend to move back to lower energy levels.
During this transition, the electrons release energy in the form of photons. - Spectrum Formation:
The emitted photons form the hydrogen spectrum.
Each transition between energy levels produces a specific wavelength or frequency of light, leading to a series of discrete lines in the spectrum.
These lines are characteristic of the hydrogen atom and can be observed in different regions of the electromagnetic spectrum, such as ultraviolet, visible, and infrared.
Series in H Spectrum
The spectrum consists of several series of spectral lines corresponding to different transitions. The most well-known series are:
- Lyman series:
These lines are produced by electron transitions to the n=1 energy level.
The series starts from higher energy levels (n₂ > 1) and terminates at n₁=1.
The lines in the Lyman series are in the ultraviolet region. - Balmer series:
These lines are produced by electron transitions to the n=2 energy level.
The series starts from higher energy levels (n₂ > 2) and terminates at n₁=2.
The lines in the Balmer series are in the visible region,
with the H-alpha line at 656.3 nm being the most prominent. - Paschen series:
These lines are produced by electron transitions to the n=3 energy level.
The series starts from higher energy levels (n₂ > 3) and terminates at n₁=3.
The lines in the Paschen series are in the infrared region. - Brackett series:
These lines are produced by electron transitions to the n=4 energy level.
The series starts from higher energy levels (n₂ > 4) and terminates at n₁=4.
The lines in the Brackett series are in the infrared region. - Pfund series:
These lines are produced by electron transitions to the n=5 energy level.
The series starts from higher energy levels (n₂ > 5) and terminates at n₁=5.
The lines in the Pfund series are in the infrared region.
These series can extend further to higher energy levels, but the lines become increasingly closer together and shift into the X-ray region.