Which of the following describes an anion?

An anion is defined as a negatively charged ion. This means that an anion occurs when an atom or molecule gains one or more electrons, which results in an overall negative charge due to the increased number of electrons compared to protons. The gain of electrons outweighs the positive charge of the protons present in the nucleus, hence creating a net negative charge.

In the context of other choices, positively charged ions are referred to as cations, and those do not describe anions. The option stating that anions have more electrons than protons reinforces the correct understanding of their nature. However, the statement that anions have no charge completely contradicts their fundamental definition, as an anion, by definition, must have a negative charge. Thus, the selection of negatively charged ions as the correct choice accurately characterizes anions.