Passage IThe equilibrium reaction has been thoroughly studiedKp = 0.1...
Step 1: Understanding the equilibrium reaction
The equilibrium reaction is:
At equilibrium, we know:
- The equilibrium constant Kp = 0.148 at 298 K.
- The total equilibrium pressure is reduced to 1.00 atm due to an increase in the volume of the container.
Step 2: Use the equilibrium expression for Kp
The equilibrium expression for this reaction is:
Where PNO2 is the partial pressure of NO2 and PN2O4 is the partial pressure of N2O4 at equilibrium.
Step 3: Let’s assume an initial amount of N2O4
Let’s assume the initial pressure of N2O4 before dissociation is P0, and the partial pressure of NO2 at equilibrium is PNO2. Let’s denote the fraction dissociated as x.
At equilibrium, the changes in pressures would be:
- The partial pressure of N2O4 will decrease by xP0.
- The partial pressure of NO2 will increase by 2xP0 (since two moles of NO2 are produced for each mole of N2O4).
Thus, the equilibrium pressures can be written as:
- PN2O4 = P0 − xP0
- PNO2 = 2xP0
Step 4: Total pressure at equilibrium
The total pressure at equilibrium is the sum of the partial pressures:
We are told that the total pressure is 1.00 atm, so:
This equation allows us to solve for P0 in terms of x.
Step 5: Apply the equilibrium constant expression
Substitute the equilibrium pressures into the Kp expression:
We know that Kp = 0.148, so:
Simplify the equation:
Now, substitute
into this equation and solve for x.
Step 6: Solve for the fraction dissociated x
After solving the equation, you will find that the fraction dissociated xxx is approximately 0.189.