Explain giving reason. NF3 is an exothermic compound but NCl3 is an endothermiccompound.

Hello Student
NCl3 is endothermic compound because of its high enthalpy of formation due to large difference in sizes of N and Cl atoms. This large difference makes N-Cl bond weak, while in NF3 the sizes of atoms are not so different, therefore N-F bond is strong and thus it is an exothermic compound.

NF3 is exothermic due to negligible and strong N F bonds while In NCl3 nitrogen can`t accommodate big sized cl atoms . so its endothermic

Dear Student,
Please find below the solution to your problem.

NCl3 is endothermic compound because of its high enthalpy of formation due to large difference in sizes of N and Cl atoms.
This large difference makes N-Cl bond weak, while in NF3 the sizes of atoms are not so different, therefore N-F bond is strong and thus it is an exothermic compound.

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