# Is Nitrate (NO3-) an example of a polyatomic ion?

You gots $N {O}_{3}^{-}$..and a Lewis structure of this anion would be of the form of …$O = \stackrel{+}{N} {\left(- {O}^{-}\right)}_{2}$...the nitrogen is quaternized and BEARS a formal positive charge....and TWO of the oxygen atoms bear a formal negative charge. The overall charge of the ion is $- 1$, and all the oxygen atoms are equivalent by resonance.
Other examples of polyatomic ions include sulfate, $S {O}_{4}^{2 -}$, perchlorate, $C l {O}_{4}^{-}$, and biphosphate, $H P {O}_{4}^{2 -}$...