What does the atomic number tell us?

Besides placement on the defines the atom of the element by defining the number of protons in the atom.

Carbon – Atomic Number 6 has 6 protons Nitrogen – Atomic NUmber 7 has 7 protons.

The proton number and the neutron number combine to provide the atomic of the element.

Carbon – 6 protons + 6 neutrons = 12 amu Nitrogen – 7 protons + 7 neutrons = 14 amu

I hope this was helpful. SMARTERTEACHER