Consider the following equilibrium at 395K:
NH4HS(s) <--> NH3(g) + H2S(g)
The partial pressure of each gas is 0.265 atm. Calculate Kc for the reaction
Kp = pNH3*pH2S
Then Kp = Kc(RT)^delta n
To calculate the value of the equilibrium constant, Kc, we need to use the partial pressures of the gases at equilibrium.
Given:
Partial pressure of NH3 (P(NH3)) = 0.265 atm
Partial pressure of H2S (P(H2S)) = 0.265 atm
The equilibrium constant expression for the reaction is:
Kc = ([NH3] * [H2S]) / [NH4HS]
Since the solid NH4HS is not included in the equilibrium constant expression as it is in a pure state, we don't need to consider its concentration.
Now, let's substitute the given values into the equation and calculate Kc:
Kc = (0.265 * 0.265) / [NH4HS]
Since the concentration of NH4HS is not given, we cannot calculate the exact value of Kc without additional information.
However, this step-by-step breakdown shows you how to set up the equilibrium constant expression using the given partial pressures.
To calculate the equilibrium constant, Kc, we need to use the equilibrium concentrations of the reactant and product species. However, in this case, we are only given the partial pressures of the gases, NH3 and H2S. Therefore, we need to convert these partial pressures to concentrations.
Since NH3 and H2S are gases, we can use the ideal gas law to convert partial pressure to concentration. The ideal gas law equation is:
PV = nRT
where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin.
To convert the partial pressures of NH3 and H2S to their respective concentrations, we can rearrange the ideal gas law equation:
n/V = P/RT
Given that the partial pressure of NH3 and H2S is 0.265 atm, and the temperature is 395K, we can substitute these values in the equation, along with the value of the ideal gas constant, R.
Using the ideal gas constant, R = 0.0821 L·atm/(K·mol), we can calculate the concentrations of NH3 and H2S.
n(NH3)/V = (0.265 atm) / (0.0821 L·atm/(K·mol) · 395 K)
n(H2S)/V = (0.265 atm) / (0.0821 L·atm/(K·mol) · 395 K)
After calculating the concentrations of NH3 and H2S, we need to determine the concentration of NH4HS. Since NH4HS is a solid, the concentration is considered to be constant and is not included in the expression for Kc.
Now that we have the concentrations, we can apply the formula for Kc for this reaction:
Kc = [NH3] * [H2S] / [NH4HS]
By plugging in the calculated concentrations of NH3 and H2S, and considering the concentration of NH4HS as constant, we can solve for Kc.