That's incorrect! A chlorine atom actually has a larger radius than a chloride ion (Cl⁻). Here's why:

* Atomic Radius: The atomic radius refers to the distance from the nucleus to the outermost electron shell of an atom.

* Ionic Radius: The ionic radius refers to the distance from the nucleus to the outermost electron shell of an ion.

Chlorine Atom: A chlorine atom has 17 electrons and 17 protons. The outermost shell has 7 electrons.

Chloride Ion (Cl⁻): When a chlorine atom gains an electron to form a chloride ion, it now has 18 electrons and 17 protons. This extra electron goes into the outermost shell, making it more negatively charged and causing a greater repulsion between the electrons. This repulsion pushes the electron shells further away from the nucleus, resulting in a larger ionic radius compared to the atomic radius.

In summary:

* Cl atom: Smaller radius (due to fewer electrons and less repulsion)

* Cl⁻ ion: Larger radius (due to more electrons and greater repulsion)