Answer: The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons. Illustrated Glossary of Organic Chemistry - Atomic radius. Atomic radius: The radius of an atom. This distance between an atom's nucleus and outer electron shell. ... Atomic radius differs with the bonding state of an atom (for example a nonbonded atom of an element versus the same element within a covalent bond). Atomic radius is determined as the distance between the nuclei of two identical atoms bonded together. The atomic radius of atoms generally decreases from left to right across a period. The atomic radius of atoms generally increases from top to bottom within a group.
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