Question

Phosphorus pentachloride decomposes according to the chemical equation:

PCl5(g)<--> PCl3(g)+Cl2(g)

Kc = 1.80 at 250 degrees Celsius

A 0.352 mol sample of PCl5(g) is injected into an empty 4.45 L reaction vessel held at 250 °C. Calculate the concentrations of PCl5(g) and PCl3(g) at equilibrium.

PCl5 = ?
PCl3 = ?

Answer 1

do the ice table
species initial final
PCl5 .352/4.45 (.352/4.45-x)
PCl3 0 x
CL2 0 x
where numbers are in moles per liter

K=x^2/(.352/4.45-x)

you know k, solve for x, then the concentrations listed on your ICE table.

Answer 2

Thank you! What did you get as answers? My answers were not correct.

Answer 3

If you will post your work someone will be glad to find the error for you.