Question

what is the covalency state of nitrogen in NO2

Answer 1

Here's the answer to your question.

Let us take oxidation state of N in NO2 is x

so

x + (-2)×2 = 0 (because the compound is neutral)

x = +4

So the oxidation number of N in NO2 is +4 and covalency is also +4

Let us consider the oxidation state of N in N2O4 is y

So

2y + (-2)×4 = 0

2y = 8

y= +4

So oxidation state of N in N2O4 is +4 and covalency is also +4.

Hope it helps :)