What is the covalence of nitrogen in `"N"_(2)"O"_(5)` ?

Explanation

Number of .O. atoms bonded to each .N. atom in `N_(2)O_(5)` is 2.5. Hence the covalency of .N. is calculated as 5, based on oxide theory. But by the examination of the structure of `N_(2)O_(5)`, one can observe that .N. forms only 4 bonds.
Its covalency in nitrogen pentoxide is 4.