The '''atomic radius''' is a rough measurement of the [[distance]] from the center of an [[atom]]'s [[nucleus]] to one edge of the atom. Atoms do not have defined shapes, so this measure can not be exact.
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The '''atomic radius''' is a rough measurement of the [[distance]] from the center of an [[atom]]'s [[nucleus]] to one edge of the atom (defined by its outer ring of electrons). As atoms do not have well-defined shapes this measure cannot be exact.