In: Chemistry
Given the following unbalanced reaction and thermodynamics infromation, what is deltaGknot rxn at 85 degrees Celcius. Please report your answer in kj/mol and to the correct number of significant figures.
C2H6 (g) + O2 (g) --> CO2 (g) + H2O (g)
deltaH values (kJ/mol): C2H6 (g) = -83.9; CO2 (g) = -394; H2O (g) = -242
deltaS values (J/mol): C2H6 (g) += 229; CO2 (g) = 214; H2O (g) = 189; O2 (g) =206
Side note: My answer was -2892.42, however it was wrong.
C2H6 (g) + O2 (g) CO2 (g) + H2O (g)
Balance the given reaction. On balancing we get:
C2H6 (g) + 7/2 O2 (g) 2 CO2 (g) + 3 H2O (g)
Go = Ho - TSo
Ho =Ho products - Ho reactants = [(-394 x 2) + (-242 x 3)] - [(-83.9)+0] = -1514 + 83.9 = -1430.1 Kj/mol
So =So products - So reactants = [(214x 2) + (3 x 189)] - [229+ (7/2 x 206)] = 428 + 567 - 950 = 45 KJ/mol
T = 85 + 273 = 358 K
Go = Ho - TSo = -1430.1 - (358 x 45) = - 17540.1 KJ/mol