Question
In $$PO_4^{3 - },$$ the formal charge on each oxygen atom and the $$P - O$$ bond order respectively are
A.
$$ - 0.75, 0.6$$
B.
$$- 0.75, 1.0$$
C.
$$ - 0.75, 1.25$$
D.
$$ - 3, 1.25$$
Answer :
$$ - 0.75, 1.25$$
Solution :
$$\eqalign{ & {\text{Bond order}} \cr & = \frac{{{\text{Number of bonds}}}}{{{\text{Number of Resonating structures}}}} \cr & = \frac{5}{4} = 1.25 \cr} $$
Three unit negative charge is being shared by four $$O$$ atoms. Formal charge $$ = - \frac{3}{4} = - 0.75$$
$$\eqalign{ & {\text{Bond order}} \cr & = \frac{{{\text{Number of bonds}}}}{{{\text{Number of Resonating structures}}}} \cr & = \frac{5}{4} = 1.25 \cr} $$
Three unit negative charge is being shared by four $$O$$ atoms. Formal charge $$ = - \frac{3}{4} = - 0.75$$