(b) Formal charge (
FC) can be calculated by using formula :
FC= (number of electrons in neutral atom)
−‌ (number of electrons in covalent bonds) - (number of electrons in lone pairs)
Formal charge on lst atom i.e., oxygen is
FC=6−‌×4−4=6−2−4=0 Formal charge on 2nd atom i.e., nitrogen is
FC=5−‌×8−0=5−4=+1 Formal charge on 3rd atom i.e., oxygen is
FC=6−‌×4−4=6−2−4=0 Hence, formal charge of atoms 1,2 and 3 in the ion
[O1=N2=O3+. is
0,+1 and 0 respectively.