Answer:
N≡N
Explanation:
The image attached shows the nitrogen compounds that are being referred to in the question.
There are certain things we ought to know in order to answer the question accurately.
The bond order of a compound is equal to the number of bonds between two atoms. The greater the bond order, the shorter the bond length between the two atoms.
N≡N has a bond order of three, this is the highest bond order among all the species listed in the question. Hence it has the shortest bond length among the trio. Hence the answer.
