The N−N bond length in N2O is 1.12 Å, slightly longer than a typical N≡N bond, which is 1.10 Å, and the N−O bond length is 1.19 Å, slightly shorter than a typical N=O bond, which is 1.22 Å. Based on these data, which resonance structure best represents N2O?

The resonance structure that best represents N₂O is ;  N=N=O

 Given that  the N-N bond is an intermediate bond, for the bond length to be longer it must posses a bond that is less than three(3) but greater than one(1) . i.e. a double bonding

 Therefore a resonance bond that posses a double bond between the N-N and N-O is the most suitable of resonance structure that will best represent N₂O. because other resonance structures will contain charges that are either greater than -1 or +1

Hence we can conclude that the structure that will best represent N₂O will be N=N=O

Learn more : link

1.solid

2.carbon dioxide

3.helium