The equilibrium constant for the reaction
PCl3(g) + Cl2(g) ⇀↽ PCl5(g)
is 35000 at 760 ◦C. At equilibrium, the partial
pressure of PCl5 was 150 bar and that of
PCl3 was 8.12 bar. Calculate the equilibrium
partial pressure of Cl2.
Answer in units of bar.
I got 5.27 but that was wrong. Help?
Probably you worked it right and left off the exponents.
The answer is 5.27E-4 bar unless that K you list is Kc and not Kp.
To solve this problem, you can use the equilibrium expression and the given equilibrium constant to set up an equation relating the partial pressures of PCl3, Cl2, and PCl5. The equilibrium expression for the reaction is:
K = [PCl5] / ([PCl3] * [Cl2])
Given that K = 35000, [PCl5] = 150 bar, and [PCl3] = 8.12 bar, the equation becomes:
35000 = 150 / (8.12 * [Cl2])
To solve for [Cl2], rearrange the equation:
[Cl2] = 150 / (8.12 * 35000)
Now, solve for [Cl2]:
[Cl2] ≈ 0.00542 bar
So, the equilibrium partial pressure of Cl2 is approximately 0.00542 bar.