# How many bonding orbitals are there in PCl_3?

$P C {l}_{3}$ has three bonding orbitals.
There is a total of 26 valence electrons in this molecule, 5 on $P$ and 7 on each $C l$ atom. Three of the $s {p}^{3}$ hybrid orbitals on $P$ overlap with one $p$ orbital on each $C l$ atom to form three bonding orbitals (occupied) and three anti-bonding orbitals (unoccupied).
The fourth $s {p}^{3}$ hybrid orbital on $P$ is a doubly occupied non-bonding orbital, as are the remaining $p$ orbitals on the three $C l$ atoms.