What would you predict for the lengths of the bonds in no2− relative to n−o single bonds and double bonds?

Single bond > Bond in NO₂  > Double bond

Explanation:

What would you predict for the lengths of the bonds in NO₂ relative to NO single bonds and double bonds?

Let's look at the Lewis structures for NO₂. As we can see, it can be represented by 2 resonant structures. We could picture it as N having a single covalent bond with each O and another single covalent bond that is divided by the two bonds. The resulting bond order is 1.5.

As a general rule, the higher the bond order (B.O.), the shorter the bond length. The rank of lengths is:

Single bond (B.O.: 1) > Bond in NO₂ (B.O.: 1.5) > Double bond (B. O.: 2)