The opposite could be idle, inactive, or quiet.
occupied
occupiedFull, occupied, overflowing...
unoccupied (really not sure just trying to help)
Yes, that is how you spell occupied.
That is the correct spelling of the word "occupied".
occupied
Vacant Available
vacancy
occupiedFull, occupied, overflowing...
The opposite of "libre" is "ocupado" in Spanish, which means "busy" or "occupied". It refers to when something is not available or free.
An atom's energy levels are orbitals which can contain 2 electrons each, assuming that they are traveling in opposite directions from each other.
unoccupied (really not sure just trying to help)
The past participle of "occupied" is "occupied." For example, "The room was occupied by other guests."
The past tense is occupied.
Each orbital can hold a maximum of 2 electrons, with opposite spins according to the Pauli exclusion principle.
occupied
...Occupied -_-