Niels Bohr
Danish physicist, 1913
The Bohr’s Model
Electron Orbits
Bohr proposed that electrons orbit the nucleus in specific, fixed paths or “shells” rather than randomly. These orbits are at certain distances from the nucleus and have fixed energies.
Quantized Energy Levels
According to Bohr, electrons can only occupy these specific orbits or energy levels. They can’t exist between these levels. This idea is known as quantization. Electrons must absorb or emit precise amounts of energy to move from one orbit to another.
Energy ABSORPTION
When an electron jumps from a higher energy orbit to a lower one, it emits energy in the form of light. Conversely, when an electron absorbs energy, it moves to a higher orbit. This explains the emission and absorption spectra observed in atomic experiments.
STable Orbits
Electrons in these fixed orbits do not lose energy and spiral into the nucleus, which was a problem in earlier models. Bohr’s model provided stability to the electron’s position in its orbit.