Niels Bohr's contribution to atomic theory explained
An overview of Niels Bohr's refinement of the Rutherford model.
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Transcript
The Rutherford atomic model was the first model to propose electrons as subatomic particles spinning around a central nucleus.
It was revolutionary, but flawed.
If electrons constantly revolved, they’d lose energy and make atoms unstable. But atoms are stable.
Someone needed to refine the atomic model.
In 1913, Niels Bohr determined that electrons don’t radiate energy as they circle the nucleus. They travel around it in fixed paths, or discrete orbits, similar to the planets orbiting the Sun.
Each orbit corresponds to a defined energy level.
The lowest, or ground state, is closest to the nucleus.
The further from the nucleus, the higher the energy level. Electrons move from a low to a high energy level--an excited state--by gaining energy.
But not just any quantity of energy!
The energy required to move to a higher energy level has to be equal to the difference in energy of the two orbits. Likewise, electrons can move from a high energy level to a low one.
When this happens, electrons emit photons -- energy released in the form of light! Bohr’s model accurately described the behavior of the hydrogen atom.
This gave scientists the information they needed to develop the current quantum mechanical model of the atom.
If electrons constantly revolved, they’d lose energy and make atoms unstable. But atoms are stable.
Someone needed to refine the atomic model.
In 1913, Niels Bohr determined that electrons don’t radiate energy as they circle the nucleus. They travel around it in fixed paths, or discrete orbits, similar to the planets orbiting the Sun.
Each orbit corresponds to a defined energy level.
The lowest, or ground state, is closest to the nucleus.
The further from the nucleus, the higher the energy level. Electrons move from a low to a high energy level--an excited state--by gaining energy.
But not just any quantity of energy!
The energy required to move to a higher energy level has to be equal to the difference in energy of the two orbits. Likewise, electrons can move from a high energy level to a low one.
When this happens, electrons emit photons -- energy released in the form of light! Bohr’s model accurately described the behavior of the hydrogen atom.
This gave scientists the information they needed to develop the current quantum mechanical model of the atom.