Answer:
ΔHf = 3301 kJ/mol
Explanation:
The standard enthalpy of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements, with all substances in their standard states.
In a reaction ΔHf = ∑ n ΔHproducts - ∑ n ΔHreagents
Where n are moles
For the reaction:
1 C₆H₆ + 7.5 O₂ → 6 CO₂ + 3 H₂O
The ΔHf = -285,8 kJ/mol × 3 - 393,5 kJ/mol×6 - [82,6 kJ/mol×1 -0kJ/mol×7,5]
ΔHf = 3301 kJ/mol
I hope it helps!
