* Na is the chemical symbol for sodium.
* Atomic Number represents the number of protons in an atom's nucleus. This number defines what element the atom is.
* +1 indicates that the sodium atom has lost one electron.
Important: Losing or gaining electrons does NOT change the atomic number. The atomic number remains the same even when an atom becomes an ion.
Therefore, the atomic number of Na+1 is still 11, the same as neutral sodium.
