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This question already has an answer here:

Bohr atom model is still the textbook content of today's high school physics.

We all know that the Bohr model is only suitable for single electron hydrogen atom, not suitable for other atoms. For example it's not suitable for Helium atom with two electrons.

The Bohr model is obviously wrong. The atomic system based on this model has no mechanical stability, atoms can not exist this way. Hydrogen atom is a coincidental exception, because it has only one electron.

According to Coulomb's law, the electrical force between proton and electron provides centripetal force, which enables the electron to run in orbit. This is a model that physicists draw from the analogy of the solar system's planetary models. One electron Hydrogen atom is OK based on this scenario.

For helium atom with two electrons, this model can not provide mechanical stability, that is, two electrons can not exist stably around the nucleus.

The reason is simple: because there is also a great force between the two electrons. The magnitude of the repelling force is in the same level with the centripetal force, this must make the helium atom unstable.

Our solar system is stable because these planets are far enough apart, compared with sun's attraction, the attractive force between planets are almost ignored. When multiple electrons move around the nuclear, the repulsive forces between them are too strong and cannot be ignored, which will definitely destabilize the atom. Atoms are not the same as solar system.

For large atoms, it is easier to understand that the strong interaction between electrons makes atoms mechanically unstable. Outside the nucleus, a group of electrons with huge repulsive force are circling. How can we make the atom exist stably without disintegration?

Another error is that the Bohr model can't make up molecules (for example, two hydrogen atoms make up hydrogen molecule). No electron can circle two nuclei at close range due to mechanical stability problem. This is similar to the reasons why binary systems cannot have close common planets.

All the assumptions based on the Bohr model that electrons rotate around two or more nuclei to form chemical bonds are impossible. Electron is not a man driven space ship that can go anywhere the driver want.

Bohr (not only him, but many physicists at that time) was misled by the planetary model and came up with an incorrect model that only applies to hydrogen atom.

The atom model suitable only for a single electron atom must not be the correct atomic structure.


In terms of atom stability, Bohr's circling model is correct only for hydrogen. Considering other ways, it's not right, it is not suitable for hydrogen atom either.

The solar system will not disintegrate and reorganize. Once formed, it will remain unchanged until sun is too hot or to burn out.

Atoms are disintegrated and recombined at any time. The ionization of hydrogen atoms does so. Ionization means that atom break up into electron and proton, whereas proton and electron close together can merge into hydrogen atom.

Bohr's circling model can not complete this dismantle and rebuild process. The recombined electrons will crash onto the proton due to Coulomb force.

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marked as duplicate by knzhou, PM 2Ring, safesphere, StephenG, Emilio Pisanty Jun 29 at 20:24

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    $\begingroup$ Possible duplicate of Where are the inaccuracies in the Bohr model of the atom? $\endgroup$ – knzhou Jun 29 at 19:18
  • $\begingroup$ Bohr's model of the Hydrogen atom's merit:it sparked the later work by Sommerfeld and Wilson, the equations of whom served Heisenberg in 1925 to delevop Quantum Mechanics. $\endgroup$ – DanielC Jun 29 at 19:44
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    $\begingroup$ IMO, it keeps being taught because it was taught before - the organizations controlling high school physics course content are not renown for their tendency towards changing things. Or to put it another way "bloody inertia" keeps it there. Bizarre as the kids get exposed to more modern theories anyway by the internet and TV. $\endgroup$ – StephenG Jun 29 at 20:14
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    $\begingroup$ I feel like it should be stressed that the Bohr model really doesn't work for hydrogen either. One benefit if it weren't taught would be a huge reduction in the number of questions on this site asking why it fails in such-and-such case (the answer is nearly always that the Bohr model is just not true). $\endgroup$ – jacob1729 Jun 29 at 20:59
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    $\begingroup$ Yes. In terms of atom stability, Bohr's circling model is correct only for hydrogen. Considering other ways, it's not right, it is not suitable for hydrogen atom either. $\endgroup$ – Cang Ye Jun 30 at 1:07
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In all likelihood, high schools continue to teach this model of the atom because it serves the purpose of being complex enough to give a "moderately accurate" intuition about the structure of matter and allows chemistry classes to at least be consistent if not completely correct. While the model is obviously incorrect, it makes sense that schools would simplify their teachings to avoid in-depth discussion of quantum mechanics and mechanical stability, not to mention the fact that in order to discuss the inaccuracies of the Bohr model, a chemistry class would have to make college-level physics a pre-requisite, and therefore an implausible task for most high school students. You might liken this simplification to the teaching of Newtonian gravity as a compromise between the accuracy and inherent difficulty of teaching general relativity instead.

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  • $\begingroup$ Amen to your answer. Deserved my up vote. $\endgroup$ – Bob D Jun 29 at 21:12
  • $\begingroup$ This is not same as Newtonian law. Newton law is applicable to all macroscopic matters. It is OK for earth and moon, OK for Mars, and OK for planets of other star planet system. $\endgroup$ – Cang Ye Jun 30 at 1:50
  • $\begingroup$ @CangYe Obviously Newtonian Mechanics is only applicable to macroscopic situations, and even then only at fractions of the speed of light. I said that you "might liken" the simplification between Einstein's gravity and our continued teaching of Newton to the choice to teach Bohr instead of more sophisticated models. $\endgroup$ – BooleanDesigns Jun 30 at 3:12
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Bohr's model in my opinion is the first mathematically approachable model for the atoms suitable to be taught to high school students. It is indeed faulty and can't explain a lot but my friend what would have happened if bohr didn't think of it at the first place it was great in a way that it could explain big questions of that time like the absorption and emission spectrum. So it is a necessary prerequisite for students to learn the things that are right for them at their age.You might think of improving the curriculum by learning other theories and models but I think math required wouldn't be easy for high school students (probably think of quantisation of angular momentum what a great thought)

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