The azide ion, n−3, is a symmetrical ion, all of whose contributing structures have formal charges. draw three important contributing structures for this ion.

The azide ion N3- can actually be represented by 3 resonance structures.

(check attached image for the structures)

Among the three, the Structure 1 is the most important one. While structure 3 almost makes no contribution due to the positive charges located on the adjacent atoms and the overall higher formal charge.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.