Nuclear Notation
- A nuclide is a group of atoms containing the same number of protons and neutrons
- For example, 5 atoms of oxygen are all the same nuclide but are 5 separate atoms
- Atomic symbols are written in a specific notation called nuclide or AZX notation
Atomic symbols in AZX Notation describe the constituents of nuclei
- The top number A represents the nucleon number or the mass number
- Nucleon number (A) = total number of protons and neutrons in the nucleus
- The lower number Z represents the proton or atomic number
- Proton number (Z) = total number of protons in the nucleus
Exam Tip
In Chemistry, the nucleon number is usually referred to as the mass number and the proton number as the atomic number
Make sure you know that the periodic table is ordered by atomic number
