The standard free energy of formation of N₂(g) at 25°C is zero. Calculate ΔG_f (25°C), in kilojoules per mol, for N₂ at 1000 atm. Assume ideal gas behavior.

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The standard free energy change for a reaction can be calculated using the equation ΔG = ΔG° + RTln(P/P°), where ΔG° is the standard free energy change, R is the gas constant (8.314 J/mol·K), T is the temperature in Kelvin, P is the pressure of the gas, and P° is the standard pressure (1 atm). Given ΔG° = 0 kJ/mol for N2O at 25°C (298 K) and wanting to find ΔG at 1000 atm, we convert the pressure to the same units as P° (atm), so P/P° = 1000 atm / 1 atm = 1000. Plugging into the equation: ΔG = 0 + (8.314 J/mol·K)(298 K)ln(1000). Converting J to kJ (1 kJ = 1000 J), the calculation gives ΔG ≈ +17.1 kJ/mol.

The Standard Free Energy of Formation of N2(g) at 25°C

The Standard Free Energy of Formation of N₂(g) at 25°C