Which of the following best defines a cation?

A cation is best defined as a positively charged ion. This occurs when an atom or molecule loses one or more electrons, resulting in a net positive charge due to the imbalance between the number of protons (positively charged) and electrons (negatively charged).

When an atom loses electrons, it becomes a cation because the loss of negatively charged particles increases the overall positive charge of the atom. Cations play a critical role in various chemical reactions and are important in fields such as electrochemistry and biochemistry.

In contrast, a negatively charged ion would be identified as an anion, which is formed when an atom gains electrons. Options regarding an uneven number of neutrons pertain to isotopes, and a neutral molecule has no overall charge, which does not align with the definition of a cation. Therefore, identifying a cation as a positively charged ion is foundational to understanding ionic behavior in chemical processes.