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Consider the reaction N₂(g) + 2O₂(g) 2NO₂(g) Using the standard thermodynamic data in the tables linked above, calculate the equilibrium constant for this reaction at 298.15K

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The value of Kp for the reaction at 298.15 K is approximately 2.49 x 10^4, while at 1173.00 K it is approximately 1.29 x 10^-4.

To calculate the value of Kp for the reaction at 298.15 K and at 1173.00 K, we need to use the equation:

Kp = exp(-ΔG°/RT)

Where ΔG° is the standard Gibbs free energy change for the reaction, R is the gas constant (8.314 J/(mol·K)), and T is the temperature in Kelvin.

First, we need to calculate the ΔG° for the reaction at each temperature using the thermodynamic data provided.

At 298.15 K:

ΔG° = ΔH° - TΔS°

ΔG° = (82.05 kJ/mol) - (298.15 K) * (219.9 J/mol-K) / 1000 J/kJ

ΔG° = 82.05 kJ/mol - 65.84 kJ/mol

ΔG° = 16.21 kJ/mol

At 1173.00 K:

ΔG° = ΔH° - TΔS°

ΔG° = (82.05 kJ/mol) - (1173.00 K) * (219.9 J/mol-K) / 1000 J/kJ

ΔG° = 82.05 kJ/mol - 258.02 kJ/mol

ΔG° = -175.97 kJ/mol

Now we can calculate the values of Kp for each temperature:

At 298.15 K:

Kp = exp(-ΔG°/RT)

Kp = exp(-(16.21 kJ/mol) / ((8.314 J/(mol·K)) * (298.15 K)))

Kp ≈ 2.49 x 10^4

At 1173.00 K:

Kp = exp(-ΔG°/RT)

Kp = exp((-(-175.97 kJ/mol)) / ((8.314 J/(mol·K)) * (1173.00 K)))

Kp ≈ 1.29 x 10^-4

The probable question maybe:-

Calculate the value of Kp for the reaction at 298.15 K and at 1173.00 K

Consider the reaction:

2N, (9) + O2(9) = 2N,0(g)

Thermodynamic data for N,O(g) are:

AH°, = 82.05 kJ/mol; S° = 219.9 J/mol -K; AG°; = 104.2 kJ/mol.

User Stefan Wuebbe
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