What process causes a neutral atom to become an ion?

A neutral atom becomes an ion through the gain or loss of electrons. When an atom gains electrons, it becomes negatively charged and is referred to as an anion. Conversely, when an atom loses electrons, it becomes positively charged, which is known as a cation. This process is fundamental to chemical reactions and interactions, as ions play a crucial role in electricity conduction, bonding, and other chemical processes.

The gain or loss of protons would fundamentally change the identity of the element itself, transforming the atom into a different element rather than simply creating an ion. Neutrons do not affect the charge of an atom; they contribute to the mass and form isotopes but do not create ions. Lastly, the gain or loss of nuclei is not a relevant concept in this context, as nuclei are the core of atoms and do not exist as separate entities in this manner. Understanding this key distinction between electrons and the other subatomic particles is essential in grasping the nature of ions and their significance in various scientific fields.