Under certain conditions, the equilibrium constant for the decomposition of `PCl_(5)(g)` into `PCl_(3)(g)` and `Cl_(2)(g)` is `0.0211 "mol"L^(-1)`.
What are the equilibrium concentrations of `PCl_(5),PCl_(3)d` and `Cl_(2)` if the initial concentration of `PCl_(5)` was `1.00 M`?

Explanation

`PCl_(5_((g))) hArr PCl_(3)_Cl_(2_((g)))`
`{:(1,0,0),((1-x),x,x):}`
`K_(C)=([PCl_(3)][Cl_(2)])/([PCl_(5)])`
`=(x)/((1-x))`
`0.0211=(x^(2))/(1-x)`
`0.0211(1-x)=x^(2)`
`0.211-0.0211x=x^(2)`
`x=0.014M`
`:. 1-x=1-0.14`
`=0.86M`
`:. 1[Pcl_(5)]=0.86M`
`:. [PCl_(3)]=0.86M`
`[PCl_(3)]=[Cl_(2)]=0.14M`