Final answer:
To calculate the N-F bond energy, determine the total energy required to break the bonds on the reactant side and the total energy released to form the N-F bond in NF3. Subtract the energy released from the energy required to find the bond energy of N-F.
Step-by-step explanation:
To calculate the N-F bond energy, we need to consider the energy changes involved in the reaction. The bond energy of N2 is 941 kJ/mol and the bond energy of F2 is 154 kJ/mol. Based on the reaction, 1/2 N2(g) + 3/2 F2(g) → NF3, the ∆H0 is -103 kJ/mol. We can use these values to determine the bond energy of N-F.
First, we calculate the total energy required to break the bonds on the reactant side:
Energy for N2 = 1/2 x 941 kJ/mol = 470.5 kJ/mol
Energy for F2 = 3/2 x 154 kJ/mol = 231 kJ/mol
Total energy required = 470.5 kJ/mol + 231 kJ/mol = 701.5 kJ/mol
Next, we calculate the total energy released to form the N-F bond in NF3:
Total energy released = ∆H0 = -103 kJ/mol
Finally, we can subtract the energy released from the energy required to find the bond energy of N-F:
N-F bond energy = Total energy required - Total energy released = 701.5 kJ/mol - (-103 kJ/mol) = 804.5 kJ/mol
Therefore, the N-F bond energy is approximately 804.5 kJ/mol, which is not one of the given options.