# Question regarding -I (negative inductive effect) producing group - Organic chemistry

1. ### sankalpmittal

786
Why is Nitrogen dioxide , a strong -I producing group that fluorine , or chlorine etc ? This must mean that NO2 is more electronegative that halogens also , but why is it so ? Is it due to resonance ? Or due to the fact that its formed from a coordinate compound HNO3 ?

I wondered for this question long , but failed to obtain answer...