OnlineCBT
Chemistry · CHEMICAL BONDING AND MOLECULAR STRUCTURE
हिन्दीGiven below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The bond dissociation enthalpy of \( \text{N}_2 \) is higher than that of \( \text{O}_2 \). Reason (R): Nitrogen has a bond order of 3 whereas oxygen has a bond order of 2, and bond enthalpy increases with increase in bond order. In the light of the above statements, choose the correct answer from the options given below:
Correct answer · Option 1
Both (A) and (R) are true and (R) is the correct explanation of (A).
Explanation
\( \text{N}_2 \) has a triple bond (bond order 3, \( \Delta_{\text{a}}H^\ominus = 946.0\text{ kJ mol}^{-1} \)) while \( \text{O}_2 \) has a double bond (bond order 2, \( \Delta_{\text{a}}H^\ominus = 498\text{ kJ mol}^{-1} \)). Increasing bond order increases bond enthalpy.
