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How does the quantum atomic model describe an electronâs location?
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The Bohr model describes the structure of atoms, in this case hydrogen.
In the quantum mechanical model, an electronâs location is not described as a precise, planetary-style orbit. Instead, it is defined by a mathematical expression known as a wave function, which represents the electron as a distribution in space rather than a localized point particle.12
Key aspects of this description include:
- Probability Distribution: The location of an electron is expressed as a probability; the likelihood of finding an electron at any specific point is proportional to the square of the amplitude of the wave function at that location.2
- Atomic Orbitals: These wave functions are called orbitals. An orbital is often depicted as a three-dimensional region where there is a 95 percent probability of finding the electron.3
- Quantum "Fuzz Ball": Because of the Heisenberg uncertainty principle, it is impossible to simultaneously know an electron's precise position and momentum. Consequently, the electron is considered to be "spread out" in space, often described as a quantum "fuzz ball" rather than a particle following a defined path.41
These orbitals are categorized by quantum numbers that determine their energy levels, shapes, and orientations in space.13