To draw the Lewis structure for tetraphosphorus (P4), we start by calculating the total number of valence electrons. Phosphorus has five valence electrons, and since there are four phosphorus atoms in P4, we have a total of 20 valence electrons.
In the Lewis structure, each phosphorus atom forms single bonds with its three neighboring phosphorus atoms. This can be represented as:
P /| P-P-P \| P
Each bond consists of a pair of electrons, which uses up 6 electrons (3 bonds), leaving 14 electrons to be distributed as lone pairs. In the structure, there are no lone pairs on any phosphorus atoms, and all the valence electrons are utilized in bonding. Consequently, each phosphorus atom has a complete octet achieved through bonding with other phosphorus atoms.
The molecular geometry of P4 is tetrahedral. The uniform structure and symmetry mean that there’s an even distribution of charge. As a result, P4 is classified as a nonpolar molecule, as there are no dipole moments due to the symmetrical arrangement of the phosphorus atoms.