1. For the reaction, #PCl_(3(g))+Cl_(2(g)) rightleftharpoons PCl_(5(g))#, #K_c = 96.2 # at 400 K. If the initial concentrations are 0.22 mol/L of #PCl_3# and 0.42 mol/L of #Cl_2#, what are the equilibrium concentrations of all species?
1 Answer
So, you know that you're dealing with an equilibrium reaction that has its equilibrium constant equal to 96.2 at a certain temperature.
The fact that
At the same time, the concentration of
I.....0.22...........0.42.................0
C.....(-x).............(-x)..................(+x)
E...0.22-x.......0.42-x................x
By definition, the equilibrium constant will be equal to
Rearrange this equation to quadratic form
This equation will produce two solutions for
The first solution is eliminated because it will result in negative equilibrium concentrations for
SIDE NOTE I've left the answers with three sig figs.