Chemistry - CHEMICAL BONDING Question with Solution | TestHub

The formal charge (FC) on an atom in a Lewis structure is given by the formula:

$FC=V-L-\frac{S}{2}$

where $V$ is the number of valence electrons, $L$ is the number of non-bonding electrons, and $S$ is the number of shared (bonding) electrons.

For oxygen, the number of valence electrons is $V=6$.

For oxygen atom $1$ (central atom):
It has $1$ lone pair ($2$ non-bonding electrons) and $3$ bonds ($6$ shared electrons).
$F{C}_1=6-2-\frac{6}{2}=+1$

For oxygen atom $2$ (left atom):
It has $2$ lone pairs ($4$ non-bonding electrons) and $2$ bonds ($4$ shared electrons).
$F{C}_2=6-4-\frac{4}{2}=0$

For oxygen atom $3$ (right atom):
It has $3$ lone pairs ($6$ non-bonding electrons) and $1$ bond ($2$ shared electrons).
$F{C}_3=6-6-\frac{2}{2}=-1$

The formal charges on oxygen atoms numbered $2$, $1$, and $3$ respectively are $0,+1,-1$.

Answer: $0,+1,-1$