Write the formal charges on atoms in (i) and carbonate ion (ii) nitrite ion.

Explanation

(i) Lewis structure of ` CO_(3)""^(2-)` ions is
Formal charge on C atom ` = 4 - 0 - (1)/(2) (8) = 0 ` , formal charge on double bonded O atom = ` 6 - 4 - (1)/(2) (4) = 0 `
Formal charge on single bonded O atom ` = 6 - 6 - (1)/(2) (2) = - `
(ii) Lewis structure of ` NO_(2)^(-)` ions is
Formal charge on N atom = ` 5 - 2 - (1)/(2) (6) = 0 ` , Formal charge on double bonded O atom ` = 6 - 4 - (1)/(2) (4) = 0 `
Formal charge on single bonded O atom `= 6 - 6 - (1)/(2) = - 1 `
Singnificance of formal charge . The main advantage of the calculation of formal charges is that it helps to
select the most stable structure, i.e., the one with least energy out of the different possibile Lewis structure. The
most stable is the one which has the smallest formal charges on the atoms.