What is the formal charge on P in PCl5?

Question

Quizplus · Accepted Answer

To calculate the formal charge on an atom in a molecule, subtract half the number of bonding electrons and all of the nonbonding electrons from the number of valence electrons. In the case of PCl5, P has 5 valence electrons and is bonded to 5 Cl atoms, each contributing 1 bonding electron. Therefore, the number of bonding electrons is 5 × 1/2 = 2.5, but since we cannot have half of an electron, we round up to 3. Additionally, P has no nonbonding electrons. Thus, the formal charge on P is 5 - 3 - 0 = 2, which is equivalent to choice letter (B). However, we notice that none of the answer choices matches with (B). This is because the correct choice, based on the question, would be the charge on P and not the formal charge on P. The charge on P in PCl5 is 0, as the compound is neutral and there are no ions present. Hence, the best choice is (D), with an explanation as stated above.

What Is the Formal Charge on P in PCl5