In the context of the periodic table, what does atomic number represent?

Atomic number is a fundamental property of an element that indicates the total number of protons found in the nucleus of an atom of that element. This number is unique to each element and determines its identity. For instance, hydrogen has an atomic number of 1, meaning it has one proton, while carbon has an atomic number of 6, indicating it has six protons.

The atomic number also plays a key role in determining the electronic configuration and chemical behavior of an element. In a neutral atom, the number of protons is equal to the number of electrons, which establishes electrical neutrality. Therefore, while it could be tempting to suggest that atomic number relates to the number of electrons, it is primarily the number of protons that defines the atomic number itself.

Neutrons, on the other hand, are not counted in the atomic number; they contribute to the atomic mass but are not directly related to the element's identity. Similarly, the mass of the element does not correspond to the atomic number but rather to the combined total of protons and neutrons in the nucleus. Thus, the atomic number specifically and unequivocally represents the number of protons in an atom.