Question

A cation or anion is called isoelectronic with another element (or ion) when it has the same number of electrons with it.

Answer 1

Atoms and ions with the same electron configuration are isoelectronic and have the same number of electrons. Isoelectronic ions and atoms have different sizes due to the number of protons. The greater the nuclear charge, the smaller the radius.

Step-by-step explanation:

Atoms and ions that have the same electron configuration are said to be isoelectronic. For example, N³, O²-, F¯, Ne, Na+, Mg²+, and Al³+ are isoelectronic species. The term isoelectronic refers to an atom and an ion of a different atom, or two different ions, that have the same electron configuration. In a series of isoelectronic ions and atoms, the size is determined by the number of protons. The greater the nuclear charge, the smaller the radius.