In this question, we need to write the total number of molecules of NO2 formed from the given amount of N2 and O2 molecules, and in the question we have:
4 N2 and 2 O2
The complete and balanced equation for this reaction is:
N2 + 2 O2 --> 2 NO2
Which means that with 2 O2 molecules, we will produce 2 NO2 molecules
The answer will be 2 NO2 molecules