Use the following standard enthalpies of formation to estimate the \(\mathrm{N}-\mathrm{H}\) bond energy in ammonia: \(\mathrm{N}(\mathrm{g}), 472.7 \mathrm{~kJ} / \mathrm{mol} ; \mathrm{H}(\mathrm{g})\), \(216.0 \mathrm{~kJ} / \mathrm{mol} ; \mathrm{NH}_{3}(g),-46.1 \mathrm{~kJ} / \mathrm{mol}\). Compare your value to the one in Table \(8.4\).

To estimate the N-H bond energy in ammonia, we can use the given standard enthalpies of formation for N(g), H(g), and NH₃(g) and follow these steps: 1. Write the balanced chemical equation for the formation of NH₃: \[ \frac{1}{2} N_{2}(\mathrm{g}) + \frac{3}{2} H_{2}(\mathrm{g}) \rightarrow NH_{3}(\mathrm{g}) \] 2. Calculate the enthalpy change (ΔH) for the reaction using the formula ΔH = ΔH(products) - ΔH(reactants): ΔH = -46.1 kJ/mol - (0.5 * 472.7 kJ/mol + 1.5 * 216.0 kJ/mol) 3. Evaluate the expression to get the total enthalpy change: ΔH = -93.55 kJ/mol 4. Calculate the N-H bond energy in ammonia by dividing the total enthalpy change by the number of N-H bonds in NH₃ (3): N-H bond energy = -31.18 kJ/mol Compare the calculated value with the one given in Table 8.4, noting that slight variations in values can occur due to different sources and experimental conditions.