Final answer:
To calculate the enthalpy change of the reaction using bond energies, identify the bonds broken and formed, apply bond energy values, sum the energies separately and then subtract the energy of formed bonds from broken bonds to get the approximate ∆H, which tells if the reaction is exothermic or endothermic.
Step-by-step explanation:
To determine the enthalpy change of the given goal reaction using the bond energies of the products and reactants, we follow these steps:
- Identify all the bonds broken in the reactants and the bonds formed in the products.
- Use the provided bond energy values for each specific bond (like the energy for H-H bonds or Br-Br bonds).
- Calculate the total bond energies for bonds broken and formed separately. The sum of bond energies for broken bonds will have a positive sign because it's energy input, while the sum for formed bonds will have a negative sign since it's energy output.
- Apply the formula: ∆H = Σ(bond energies of broken bonds) − Σ(bond energies of formed bonds).
This calculation will yield the approximate enthalpy change for the reaction, indicating whether the process is exothermic (energy releasing, ∆H negative) or endothermic (energy absorbing, ∆H positive).
If a bond energy diagram is needed, it should illustrate the energies of reactant bonds on the left, product bonds on the right, and the approximate energy change as a vertical arrow pointing up for endothermic and down for exothermic reactions.