Atomic radius

Atomic radius is a measure of the size of an atom, specifically the distance from its nucleus (center) to the outermost electrons. Think of it as the atom’s “reach” or “boundary.” The size can vary depending on the type of element and its state. Generally, atoms of elements farther down a group on the periodic table are larger because they have more electron shells. Conversely, atoms across a period from left to right tend to get smaller because the increasing positive charge pulls electrons closer to the nucleus. Atomic radius helps scientists understand how atoms interact and bond with each other.