Question

What charge anion will phosphorus typically form?

A) -1
B) -2
C) +1
D) +2

Answer 1

Phosphorus typically forms a -3 charged anion after gaining three electrons, resulting in a full octet.

Step-by-step explanation:

The charge on an anion formed by phosphorus is typically -3. Phosphorus has 5 valence electrons and requires 3 more electrons to complete its octet and achieve a noble gas configuration. In forming an anion, phosphorus gains 3 electrons which results in the anion having a 3- charge.

This is based on the tendency of atoms to achieve a stable electronic arrangement; gaining 3 electrons gives phosphorus a full set of 8 valence electrons, akin to that of Argon. The electron configuration of a phosphorus atom is [Ne]3s23p3, and after gaining 3 electrons to form the anion, it becomes [Ne]3s23p6 or [Ar], reflecting the noble gas it mirrors in terms of stability. This is more stable for the atom and is preferred in terms of energy states.