How many electrons in the nitrite ion, #NO_2^(-)#?

1 Answer
Apr 30, 2016

#(O=)N-O^-#

Explanation:

No. of valence electrons: #=2xx6+5+1=18#.

So around each atom (from left to right above), there are 6, and 5, and 7 valence electrons. Because there are 7 valence electrons around the rightmost oxygen (i.e. 9 electrons in total including the inner shell electrons), this oxygen has a formal negative charge.

Of course there is a resonance isomer: #""^(-)O-N(=O)#.

The neutral nitrogen atom has a formal lone pair in each mesomer.

How would you describe the structure of this ion based on VSEPR?