Practice: Determine the electron configuration for the Cl– ion.
The Octet Rule states that main-group elements will generally form enough bonds to obtain 8 electrons in their valence shell.
Concept #1: Ions (Octet Rule)
Example #1: How many electrons must the magnesium atom (Z =12) lose in order to obtain a filled outer shell?
Concept #2: Electron Configurations (Cations)
For a metal cation, first remove electrons from the highest shell number (n).
Example #2: Write the condensed electron configuration for the Na+ ion.
Example #3: Write the full electron configuration for the N3– ion.
For a non-metal anion, add electrons to the orbital with available space.
Practice: Determine the electron configuration for the Cl– ion.
