Electron Structure of Atoms

The electron structure of the atom is very complex; discoveries concerning the physical properties of electrons and the chemical reactions that take place between them have led to countless breakthroughs in modern physics and chemistry, such as the invention of nuclear power.

History

Key contributors to these theories and discoveries were English chemist/physicist John Dalton (1766 to 1884), U.S. chemist Gilbert Newton Lewis (1875 to 1946), and Danish physicist Niels Bohr (1885 to 1962).

Physical Properties

The electrons of an atom are always in motion, following three-dimensional wave patterns of varying size and energy intensity, depending on their relative position to the nucleus. These wave patterns are called orbitals and contain either a pair of electrons or just one.

Energy Properties

The farther removed the orbital is from the nucleus, the higher the energy level it has. The lowest energy level contains one orbital, while the highest may contain up to four.

Chemical Properties

An atom is stable when it has its outermost level of orbitals filled or completely empty of electrons; an atom is least stable when it is half-full. In this latter state, atoms are the most reactive and have the greatest tendency to bond.

Fun Facts

As you shift from the left to the right on the periodic table, the amount of electrons in the valence shell increases from only one to completely full.

References

• The Electronic Structure of Atoms
• An Introduction to the Electronic Structure of Atoms and Molecules

Resources

• The Electronic Structure of Atoms