Electronic Configuration

Electronic Configuration

All noble gases have completely filled valence shells — helium is $1s^2$ and every other member has the general configuration $ns^2np^6$ (e.g. neon $2s^22p^6$, argon $3s^23p^6$). This closed-shell, fully-paired arrangement is the most stable electronic configuration possible for a period.

• Because the octet (or duplet for He) is already complete, these atoms have very little tendency to gain, lose or share electrons, which is the root cause of their chemical inertness.
• The stable configuration also gives them the highest ionisation enthalpies in their respective periods and positive electron gain enthalpies (they resist adding an electron). …