What happens to sodium atoms when they form sodium ions?

When sodium atoms form sodium ions, they lose electrons. This process occurs because sodium is an alkali metal with one electron in its outermost shell. By losing this single electron, sodium achieves a stable electronic configuration similar to that of the noble gases, which have filled outer electron shells. This transfer results in a positively charged sodium ion (Na+), as the atom now has more protons than electrons.

The behavior of sodium atoms is driven by the tendency to achieve stability through this loss of an electron, which lowers their energy state. In contrast, gaining or sharing electrons would lead to different types of ions or covalent bonding, which is not the case with sodium ions. Hence, the choice that sodium atoms lose electrons when forming sodium ions accurately describes the chemical behavior of sodium.