2NF3(g) yields N2(g) + 3F2(g)
When 2.06 mol of NF3 is placed in a 2.00L container and allowed to come to equilibrium at 800K, the mixture is found to contain 0.0227 mol of N2. What is the value of Kp at this temp?
1.91 X 10-3
1.73 X 10-6 (think this is it)
4.43 X 10-7
1.83 X 10-3
I didn't get that. Post your work and I'll look for the error.
I think I tried to do the ICE and got...
2.06/2.00=1.03 M
0.0227/2.00=0.0114 M
but got lost after that and ended up with 1.73 X 10-6...I am really struggling on these problems...
I think you started out wrong. The problem gives as Kp and you are calculating, by mols/L, the concn. You put pressures in Kp and concns in Kc.
........2NF3 ==> N2+ 3F2
I......2.06mols...0....0
C.,.....-2x.... .x....3x
E.....2.06-x......x....3x
The problem tells you that x(N2) is 0.0227 mols. That makes F2 = 3*0.0227 and mols NF3 = 2.06- (2*0.0227)
Now convert 0.0227 to pressure using PV = nRT and do the same to find pressure of F2 and NF3. The substitute into Kp expression and solve for Kp.
My answer was 0.00190
To find the value of Kp at the given temperature, we can use the expression for Kp for the given reaction:
Kp = (p(N2))^1 * (p(F2))^3 / (p(NF3))^2
First, we need to determine the partial pressures of each gas in the mixture.
Given:
Initial amount of NF3 = 2.06 mol
Final amount of N2 = 0.0227 mol
Volume of the container = 2.00 L
Using the ideal gas law, we can calculate the partial pressures:
p(NF3) = (moles of NF3 / total volume) * R * T
p(N2) = (moles of N2 / total volume) * R * T
p(F2) = (moles of F2 / total volume) * R * T
Where R is the ideal gas constant and T is the temperature in Kelvin.
Since we are given the temperature (800K) and the volume (2.00L), we can perform the calculations. R = 0.0821 L*atm/(mol*K).
p(NF3) = (2.06 mol / 2.00 L) * (0.0821 L*atm/(mol*K)) * (800 K)
p(N2) = (0.0227 mol / 2.00 L) * (0.0821 L*atm/(mol*K)) * (800 K)
p(F2) = (3 * 0.0227 mol / 2.00 L) * (0.0821 L*atm/(mol*K)) * (800 K)
Evaluate the above expressions to calculate the partial pressures.
p(NF3) = 1.697 atm
p(N2) = 0.0186 atm
p(F2) = 0.0557 atm
Now substitute these values into the expression for Kp to find the value of Kp at 800K.
Kp = (0.0186)^1 * (0.0557)^3 / (1.697)^2
Evaluate this expression to find the value of Kp.
Kp ≈ 1.73 * 10^-6 (rounded to nearest significant figure)
Therefore, the correct answer is 1.73 * 10^-6.