Let's take the general equilibrium reaction:
$wA+xBharryC+zD$
In which A, B, C and D are and w,x,y,z are coefficients.
To determine the equilibrium constant, we write:
$K=([C]^yxx[D]^z)/([A]^wxx[B]^x)color(white)(aaaa)color(white)(color(blue)(1.)/color(blue)(2.)$
The equilibrium constant says something about the proceeding of the reaction: does it favour the forward reaction or the backwards reaction? The blue numbers represent the concentration of the two sides:
- "Combined concentration products"
- "Combined concentration reactants"
We have given that $K=100$, this means that side 1 must be a larger number than number 2. Only then will K be larger than 1. This means that the combined concentration of side 1 (products) is larger than the combined concentration of side 2.
Therefore the reaction is favoured to the right side (the product side). Since K=100 is pretty big, the reaction will probably go almost into completion.
By following this method, you can figure out that
K>>1 $color(white)(aa)$ $color(blue)(|) $Product favored $color(white)(aaa)$ $color(blue)(|)$Close to completion
K>1 $color(white)(aaa)$ $color(blue)(|) $Product favored$color(white)(aaa)$ $color(blue)(|)$ Very little
K=1 $color(white)(aaa)$ $color(blue)(|) $Equilibrium$color(white)(aaaaaaa)$ $color(blue)(|)$-
K<1 $color(white)(aaa)$ $color(blue)(|) $Reactant favored$color(white)(aaa)$ $color(blue)(|)$Very little
K<<1 $color(white)(aa)$ $color(blue)(|) $Reactant favored$color(white)(aaa)$ $color(blue)(|)$Close to completion
