Question

Write the Lewis structure for the diatomic molecule P2, an unstable form of phosphorus found in high-temperature phosphorus vapor.

a) P=P
b) P≡P
c) P-P
d) P:X:P

Answer 1

The Lewis structure for P2 is option b) P≡P, which represents two phosphorus atoms joined by a triple bond, because each atom shares three pairs of electrons to achieve a stable octet.

Step-by-step explanation:

To write the Lewis structure for the diatomic molecule P2, we start by considering the number of valence electrons for phosphorus. Phosphorus, being in group 15 of the periodic table, has 5 valence electrons. Since the molecule is P2, we have a total of 10 valence electrons to work with.

The molecule is composed of two phosphorus atoms sharing electrons to fill their outer shell. Each phosphorus atom will need 3 more electrons to complete its octet, leading them to form a triple bond with each other and one lone pair of electrons on each atom, giving us the structure P≡P. This is also reinforced by the fact that P2 has a similar electronic structure to N2, which is well-known to have a triple bond.

Hence, the correct option for the Lewis structure of P2 is b) P≡P, which represents a phosphorus molecule with a triple bond.