atom

CE5

Bohr-Rutherford atom

CE5

Probability distribution of the electron in the hydrogen atom: A. Ground state B. Highly excited state

atom [Gr.,=uncuttable (indivisible)], basic unit of matter; more properly, the smallest unit of a chemical element having the properties of that element.

Sections in this article:

• Introduction
• Contemporary Studies of the Atom
• Discovery of the Atom's Structure
• From Dalton to the Periodic Table
• Early Atomic Theory
• Atomic Weight and Number
• The Electrons
• The Nucleus
• Structure of the Atom
• Bibliography

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