How is a sodium ion formed?

When a sodium atom (Na) loses one electron from its outermost shell, it becomes a sodium ion (Na+). A neutral sodium atom has an atomic number of 11, meaning it has 11 electrons orbiting the nucleus. In its neutral state, it has the same number of protons and electrons, resulting in a net charge of 0. Because sodium is a metal, it tends to lose electrons to achieve a stable electron configuration. Sodium has one electron in its outermost shell. Once sodium loses its outer electron it results in a positively charged ion (Na⁺). The sodium ion now has 10 electrons, and its electron configuration becomes similar to that of a noble gas (neon), which has a stable configuration of 10 electrons in its outer shell.