Final answer:
When sodium loses an electron, it becomes a positively charged ion called a cation, specifically a sodium cation (Na+). This process creates an electrical imbalance due to more protons than electrons in the atom.
Step-by-step explanation:
After sodium loses an electron, it becomes a cation.
Sodium (Na) is an element that has eleven protons and eleven electrons, making it electrically neutral. When it loses an electron, there is an imbalance because there are now more protons than electrons, which results in a positive charge. This process is often represented by the equation Na → Na+ + e−. The sodium ion that forms after electron loss is denoted as Na+. Atoms, or groups of atoms, that have a positive charge are known as cations.
The transformation of neutral sodium into a sodium cation is a common example of this process, which leads to the stabilization of the atom's electron configuration, often reaching a noble gas configuration with a full octet in its outermost shell. The creation of a sodium cation demonstrates the fundamental concept of ion formation and is particularly important in chemical reactions, such as those that occur in batteries and during the conduction of nerve impulses in biological systems.