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Bohr Model of an Atom

Bohr Model of an Atom

Author: Katie Smith

To review the Bohr model of an atom.
To create Bohr Model diagrams for various representative elements.
To evaluate the number of valence electrons using a Bohr model.

This packet includes a video explaining the Bohr model and how to create and use Bohr model diagrams, as well as practice problems.

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Introduction to the Bohr Model

While the Bohr model doesn't represent our most current understanding of the structure of an atom, it does give us a good way to understand and explain several patterns between atoms and other aspects of atomic structure.  In this model, electrons exist in specific, quantized energy levels, known as shells.  The number of electrons in each shell is dictated by the rule 2n2, where n is the principal quantum number

When drawing a Bohr model representation for an atom, electrons should be distributed by beginning in the lowest energy shell (n=1), adding electrons until that shell is full, and then moving to the next lowest energy shell (n=2).  The outermost occupied shell is referred to as the valence shell, and electrons within this shell are called valence electrons.  All other electrons are known as core electrons -- they are closer to the nucleus (or the 'core' of the atom) than the valence electrons.

The Bohr Model of an Atom

Practice Problems