Question

What is the oxidation state of Phosphorus in $P{Cl}_3$?

• A. $+5$
• B. $+3$
• C. $+1$
• D. $-3$

Answer 1

The correct option is B $+3$

The oxidation state of $P$ in $P{Cl}_3$ is $+3$.
Each Chlorine atom has an oxidation number of $-1$. There are three chlorine atoms, hence the total oxidation number of the Chloride ions in $-3$. ${PCl}_3$ molecule is neutral. Hence the oxidation number of Phosphorus should be $+3$