Answer:
The bond energy of F–F = 429 kJ/mol
Explanation:
Given:
The bond energy of H–H = 432 kJ/mol
The bond energy of H–F = 565 kJ/mol
The bond energy of F–F = ?
Given that the standard enthalpy of the reaction:
H₂ (g) + F₂ (g) ⇒ 2HF (g)
ΔH = –269 kJ/mol
So,
ΔH = Bond energy of reactants - Bond energy of products.
–269 kJ/mol = [1. (H–H) + 1. (F–F)] - [2. (H–F)]
Applying the values as:
–269 kJ/mol = [1. (432 kJ/mol) + 1. (F–F)] - [2. (565 kJ/mol)]
Solving for , The bond energy of F–F , we get:
The bond energy of F–F = 429 kJ/mol