| A | B |
|---|
| The family or group number | tells you the number of valence electrons |
| The period number | tells you the number of energy levels outside the nucleus of the atom |
| The AMU# | tells you the total mass of the atom and the combined number of protons and neutrons found in the nucleus of the atom |
| The Atomic # | tells you the number of protons found in the nucleus of the atom |
| AMU# minus the Atomic # | the number of neutrons in the nucleus of the atom |
| The # of protons is equal to the # of electrons | because all atoms are balanced |
| The first energy level or quantum has two and only two electrons | Bohr Model Rule #1 |
| The second energy level or quantum can have a maximum of 8 electrons | Bohr Model Rule #2 |
| The valence quantum level or last energy level of an atom contains the family or group # of electrons with a maximum of 8 | Bohr Model Rule #3 |
| Shorthand for the elements name | chemical symbol |
| Found under the chemical symbol foreach element on the periodic chart | element name |
