# What is the total number of valence electrons on a phosphite ion PO_3?

Feb 16, 2017

In $\text{phosphite ion}$, $\left(H O\right) P {O}_{2}^{2 -}$.............??

#### Explanation:

Around the central phosphorus atom, there are 5 electrons: $3 \times O - P$ bonds, and one phosphorus centred lone pair. Around each anionic oxygen atom, there are 7 electrons, i.e. 3 lone pairs, and ONE electron from the $P - O$ bond. You can count them up.