Posted by Cathy on .
If the equilibrium concentrations are [PCl5] = 1.0M, [Cl2] = 0.10M, what is the equilibrium constant value?
PCl5(g) <> PCl3(g) + Cl2(g)
Would you mind showing the calculations Please. I've been working on this problem over an hour now. Not certain if I am working it correctly Thank you so much.

Chemistry 
DrBob222,
In the future you should realize that you could show your work and we could look at it in a jiffy and know what is right or wrong. As it is, you work it out, post a NEW question, we work it, type it, post it. THEN YOU COMPARE IT WITH YOUR NOTES. All of this takes too much time FROM US. Many times we don't have the time to work it and do all that typing so we don't answer the question. However, if YOU take the time to type it, we can respond quickly. Having said all of that I have the time tonight so here is how you do it.
.........PCl5 ==> PCl3 + Cl2
E........1.0M......x.....0.10M
If Cl2 is 0.10M, then PCl3 MUST be 0.10M also. Then
Kc = (PCl5)/(Cl2)(PCl3)
Kc = (1.0)/(0.1)(0.1)
Check my work to make sure there are no typos.
Kc = 100