What is the compound formula for arsenic monophosphide?

1 Answer
Jul 15, 2018



Arsenic monophosphide is a covalent compound made from Arsenic and Phosphorus. Few reasons that point to why it's a covalent compound:

  • The presence of prefix ("mono"). Only covalent compound naming uses prefixes. Ionic compound naming does not involve prefixes (mono, di, tri, tetra, etc)
  • Arsenic is a metalloid and phosphorus is a nonmetal
  • Electronegativity of Arsenic is 2.18 while Phosphorus is 2.19. The difference of their electronegativity is very small, making the bond that holds them together a nonpolar covalent bond.

First part of the name, arsenic:

  • No changes made to the name of the first element when naming covalent compound.
  • Since there's no prefix in front of Arsenic, that means there's only 1 of it in the formula as there's no need to use the prefix "mono" for the first element.
  • chemical symbol: As

Second part of the name, monophosphide:

  • the name of the second element in covalent compound is modified to end with "ide". In this case, the name Phosphorus is modified to become phosphide .
  • The prefix "mono" represents 1. That means there's 1 Phosphorus in the formula.
  • chemical symbol: P

Putting together the formula from the name: AsP