Chapter 4, Problem 4E.8E

(a)

Interpretation Introduction

Interpretation:

The difference in the bond enthalpies of $\text{NO}$ and ${\text{NO}}_2$ molecule has to be explained.

Concept Introduction:

The bond enthalpy is the physical quantity use to measure the strength of chemical bond.  The bond enthalpy of a reaction is the difference between the standard bond enthalpies for reactant and that of the product.  The breaking of bond is always the endothermic process; however the formation of bond is the exothermic process.

(b)

Interpretation Introduction

Interpretation:

The reason for the same bond enthalpies of two bonds in ${\text{NO}}_2$ has to be explained.

Concept Introduction:

Same as part (a).