Question

select the atom which does not require 8 electrons in its outermost shell in order to be happy.
oxygen
chlorine
helium
potassium
rewatch

Explanation:

The octet rule states that most atoms strive for 8 electrons in their outermost shell for stability, but noble gases with a full valence shell (like Helium, which has 2 electrons in its only shell, a full outer shell) don't follow this. Oxygen, Chlorine, and Potassium follow the octet rule (Oxygen needs 2 more to reach 8, Chlorine needs 1, Potassium gives away 1 to reach a stable octet in the previous shell). Helium's outer shell is full with 2 electrons, so it doesn't need 8.

Answer:

Helium