The work function is the energy required to remove an electron from an atom on the surface of a metal. How does this definition differ from that for ionization energy?

The work function (\(\Phi\)) is the minimum energy required to remove an electron from the surface of a metal atom, depending on the type of metal and its surface condition. In contrast, ionization energy is the energy required to remove an electron from a gaseous atom or ion and is a property of individual elements. The processes involved in both phenomena are different, with work function focusing on the interaction between electrons and the metal surface, while ionization energy considers the interaction between electrons and the nucleus of the atom or ion. Work function is a property of metals, while ionization energy applies to any element. Generally, work function values are lower than ionization energy values, as electrons on the metal surface are loosely bound and more easily removed than electrons tightly bound to atoms in the gaseous state.