What is the equilibrium constant "Kp" at 200 C for the reaction below:

Question

P4(s) + 6 Cl2(g) --><-- 4 PCL3(l)

Given the following at 200 C

P4(s)+ 10 Cl2(g) --><-- 4 PCl5(s) Kc=8.12
PCl3(l)+ Cl2(g) --><-- PCl5(s) Kc=0.771

Answer: 6.7*[10^(-9)]

not sure what to do.

I know Kp=Kc(RT)^(delta n)
but the fact that they gave me two Kc values is confusing. Am I supposed to use those to somehow find the concentrations of the gaseous compounds?

Also, is "delta n" just the "final n" - "initial n" for the first reaction given (i.e. -3 or -6 depending on whether or not non-gasses count for "delta n" or not)?

Thank you in advance

Answer 1

See your other post on this.