- NF3 is an exothermic compound whereas NCl3 is not. WHY?
- NH3 is a stronger base than PH3. WHY?
The instability of NCl3 is due to the weak NCl bond. This is due to the large difference in the size of nitrogen and chlorine atoms. On the other hand, atoms of both nitrogen (75 pm) and fluorine (72 pm) are small sized. Thus, bonding in NF3 is quite strong and it is an exothermic compound.