Explanation:
Contributing structures are the resonating structures which are formed due to the delocalization of electrons in a molecule.
The azide ion that is
, is a symmetrical ion, all of whose contributing structures have formal charges.
Lone pair of central nitrogen atom in azide ion is in conjugation with the neighboring nitrogen atoms.
Contributing structures of azide ion are drawn in the image attached.
In a dilute acid solution most if not all of the molecules will split into ions.
For example HCl is a strong acid and 100% of the molecules will split into
H+ & Cl-
in a weak acid solution only a portion of the molecules will turn into ions because the ionization percentage isn't as large. Which will essentially leave a high percentage of un-reacted molecules
The nonmetal elements have a negative charge.