The typical distance between N and O atoms when they are in a single bond is 136 pm, and 120 pm when they are in a double bond. Which of the following bond lengths would be reasonable for the distance between the N and O atoms in NO2- .
a. 145 pm
b. 136 pm
c. 128 pm
d. 120 pm
1 answer
Well, it isn't a single bond so you wouldn't expect b. It isn't a double bond so you wouldn't expect d. Since it is between a double and a single bond we wouldn't expect it to be LARGER (not a).