Here's why:
* Atomic Number: This number represents the unique identity of an element.
* Protons: These are positively charged particles located in the nucleus of an atom.
* Unique Identity: Every element has a specific and fixed number of protons. This number defines the element. For example, all carbon atoms have 6 protons, all oxygen atoms have 8 protons, and so on.
In summary: The atomic number is directly tied to the number of protons in an atom, which, in turn, defines the element.
