Answer:
Phosphorus can form a P4 white phosphorus tetrahedron because it can form three bonds. The most stable allotrope of phosphorus, red phosphorus, is a cross-linked, polymeric chain of atoms.
- P has a high atomic size and a low tendency for forming triple bonds. It can make a tetra-atomic P4 molecule by sharing valency electrons with three other P atoms to complete its octet.
- White phosphorus is less stable and therefore, more reactive than the other solid phases under normal conditions because of angular strain in the P4 molecule where the angles are only 60°. It readily catches fire in the air to give dense white fumes of P4O10.
