Calculate the equilibrium constant at 25 C for
CH4 + 2 H2O --> CO2 + 4H2
given:
delta G for CH4 = -50.81
H2O = -228.6
CO2 = -394.4
H2 = 0
First, calculate DGo for the reaction. That is
DGorxn = (n*DGoproducts)-(n*DGoreactants)
Then DGo = -RTlnKp
To calculate the equilibrium constant (K) at 25°C for the given reaction, we need to use the equation:
ΔG° = -RT ln(K)
where ΔG° is the standard Gibbs free energy change for the reaction, R is the ideal gas constant (8.314 J/(mol·K)), T is the temperature in Kelvin, and ln(K) is the natural logarithm of the equilibrium constant.
Given that the temperature is 25°C, we need to convert it to Kelvin:
T = 25 + 273.15 = 298.15 K
Now we can substitute the values into the equation and solve for ln(K):
-50.81 = -8.314 * 298.15 * ln(K)
To solve for ln(K), rearrange the equation:
ln(K) = -50.81 / (-8.314 * 298.15)
ln(K) ≈ 0.083
To find K, we need to take the exponential of both sides:
K ≈ e^0.083
Using a calculator, we can find:
K ≈ 1.086
Therefore, the equilibrium constant at 25°C for the given reaction is approximately 1.086.