1. Starting Point: Chlorine Atom
* Chlorine (Cl) has an atomic number of 17, meaning it has 17 protons and 17 electrons.
* Its electronic configuration is: 1s² 2s² 2p⁶ 3s² 3p⁵
2. Formation of the Chloride Ion
* Chlorine gains one electron to achieve a stable octet (8 electrons) in its outermost shell.
* This creates a negative charge, resulting in the chloride ion (Cl⁻).
3. Electronic Configuration of Chloride Ion
* The chloride ion's electronic configuration becomes: 1s² 2s² 2p⁶ 3s² 3p⁶
Simplified Representation:
* The chloride ion has a full outer shell with 8 electrons (2 in the 3s orbital and 6 in the 3p orbitals).
* This gives it a stable, noble gas configuration similar to Argon (Ar).
Key Points:
* The chloride ion is negatively charged because it has gained one electron.
* Its electronic configuration is the same as Argon, making it very stable.
* This stability is why chloride ions are common in ionic compounds.
