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Consider the following reaction: 4 NH3(g) + 5 O₂(g) — 6 H₂O(g) + 4 NO(g) Calculate AG at 547 K for a mixture of 2.3 bar NH3(g), 3.0 bar O₂(g), 4.9 bar H₂O(g), and 3.6 bar NO(g). State whether or not the reaction is spontaneous at these conditions. **AG° values can be found in textbook appendix** O-929 kJ/mol; spontaneous -929 kJ/mol; nonspontaneous O 929 kJ/mol; spontaneous 929 kJ/mol; nonspontaneous​

User Mike Walsh
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To calculate the AG for the reaction at 547 K for a mixture of 2.3 bar NH3(g), 3.0 bar O₂(g), 4.9 bar H₂O(g), and 3.6 bar NO(g), you can use the following equation:

AG = ∑nG°(products) - ∑nG°(reactants)

where ∑n is the sum of the stoichiometric coefficients of the reactants and products, and G° is the standard Gibbs free energy of the species.

The standard Gibbs free energy of a species can be calculated using the following equation:

G° = G°(298 K) + RTln[P/P°]

where G°(298 K) is the standard Gibbs free energy of the species at 298 K, R is the gas constant (8.314 J/mol*K), T is the temperature in kelvins, P is the pressure of the species, and P° is the standard pressure (1 bar).

Plugging in the values, we get:

AG = (6 H₂O + 4 NO - 4 NH₃ - 5 O₂)

= (6 H₂O - 4 NH₃ - 5 O₂ + 4 NO)

= (6 H₂O - 4 NH₃ + 4 NO - 5 O₂)

= (6 H₂O + 4 NO - 4 NH₃ - 5 O₂)

= 6 G°(H₂O) + 4 G°(NO) - 4 G°(NH₃) - 5 G°(O₂)

= 6(-242.2 kJ/mol) + 4(-90.3 kJ/mol) - 4(-45.9 kJ/mol) - 5(-497.1 kJ/mol)

= (-1453.2 kJ/mol)

Therefore, AG for the reaction at 547 K for a mixture of 2.3 bar NH3(g), 3.0 bar O₂(g), 4.9 bar H₂O(g), and 3.6 bar NO(g) is -1453.2 kJ/mol.

Since AG is negative, the reaction

User Erre Efe
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