What is the equilibrium concentration of each of the substance in the equilibrium when the initial concentration of `ICl` was `0.78 M`?
`2ICl(g) hArr I_(2)(g)+Cl_(2)(g), K_(c)=0.14`

Explanation

Suppose at equilibrium , the molar concentration of both `I_(2)(g)` and `CI_(2)(g)` is x `mol L^(-1).`
`{:(,2ICI(g) ,hArr, I_(2)(g) ,+, CI_(2)(g)),("Initial molar conc"., 0.78 M,,0,,0),("Eqm, molar conc.",(0.78-2x)M,,x,,x):}`
`K_(c) =[[I_(2)(g)][CI_(2)(g)]]/[[ICI(g)]^(2)] =((x)xx(x))/((0.78 -2x)^(2))`
`(x)/((0.78 -2x))=(0.14)^(1//2) =0.374 " or " x = 0.374 (0.78 -2x)`
`x= 0.292-0.748 " or " 1.748 x= 0.292 , x = (0.292)/(1.748) =0.167`
`[ICI]= (0.78-2xx0.167) =(0.78 -0.334) = 0.446 M`
`[I_(2)] =0.167 M , [CI_(2)] =0.167M.`