Answer
Formal charge on nitrogen = 1
Formal charge on oxygen = -1
Work Step by Step
We know,
formal charge = no. of valence electrons - (no. of nonbonding electrons + 1/2 no. of shared electrons)
Formal charge on nitrogen = 3 - (0 + 1/2*8) = 1
Formal charge on oxygen = 6 - (6 + 1/2*2) = -1
