Question

The enthalpy changes of formation of the gaseous oxides of nitrogen ($N_{2}O$ and NO) are positive because of:

• A. the high bond energy of the nitrogen molecule
• B. the high electron affinity of oxygen atoms
• C. the high electron affinity of nitrogen atoms
• D. the tendency of oxygen to form $O^{2-}$

Answer 1

Answer: (A)

the high bond energy of the nitrogen molecule

The enthalpy changes of formation of the gaseous oxides of nitrogen are positive because of: the high bond energy of $N\equiv N$, more heat is absorbed to break up $N_2$ molecule.
Option A is correct.