What does the atomic number of an element represent?

The atomic number of an element is a fundamental property that represents the number of protons found in the nucleus of an atom. This is a critical characteristic because it determines the identity of the element; for example, all atoms with an atomic number of 6 are carbon atoms, while those with an atomic number of 8 are oxygen atoms. The atomic number also influences the chemical behavior of the element, as it dictates the number of electrons in a neutral atom, which in turn affects how the atom interacts with other atoms.

Understanding the atomic number is key to the periodic table, where elements are arranged based on increasing atomic numbers. This arrangement reveals patterns in element properties and helps predict how they will react in chemical reactions. For these reasons, the atomic number is essential in both chemistry and physics, serving as a primary identifier for each element.