This principle states that electrons fill up the lowest energy levels first before moving on to higher ones. It's like filling up the front rows at a concert before letting people into the back rows.
This principle says that no two electrons can have identical quantum states. Imagine it as each person having their own unique seat at the wedding; no two people can sit in exactly the same spot!
Hund's rule states that every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied. It’s like ensuring each room in a house has one occupant before anyone gets a roommate!