Which element has three half-filled orbitals in the 3p level?

Phosphorus Phosphorus is in group 15 period 3 in the periodic table hence it is in atomic number 15. Phosphorus electronic configuration is 1S2 2S2 2P6 3S2 3P3 or [Ne] 3S2 3P3

From the electronic configuration of phosphorus the 3p3 sub level is unfilled since the p orbital can hold a maximum of 6 electrons.

Phosphorus is the element which has 3 half-filled orbitals in 3p level.

Some periodic table characterization of phosphorus is given below:

As the 3p orbital can contain 6 electron and according to above given electronic configuration of phosphorus, 3p has 3 electrons, means half filled.

it is the most commonly accepted one