Question

what is the iupac name of the ion formed by phosphorus?
a) phosphide(iii) ion
b) phosphoide
c) phosphide
d) phosphorus(iii) ion

Explanation:

Phosphorus forms an anion by gaining electrons. The IUPAC - approved name for the anion formed by phosphorus is phosphide. There is no need for the (III) in the name as the charge of the phosphide ion is well - known without it, and 'phosphoide' is an incorrect term.

Answer:

C. Phosphide