Question

Consider the following generic reaction. A 2 B ( g ) − ⇀ ↽ − 2 A ( g ) + B ( g ) The initial concentration of A 2 B is 0.87 M and the initial concentrations of A and B are assumed to be zero. What is the equilibrium constant expression ( K c ) , if the equilibrium concentration of B is represented by x ?

Answer 1

Answer : The equilibrium constant expression will be
`K_c=(4x^3)/((0.87-x))`

Solution :

Equilibrium constant : It is defined as the equilibrium constant. It is defined as the ratio of concentration of products to the concentration of reactants.

The given equilibrium reaction is,

`A_2B(g)\rightleftharpoons 2A(g)+B(g)`

Initially conc. 0.87 0 0

At equilibrium (0.87-x) 2x x

The expression of
`K_c` will be,

`K_c=([A]^2[B])/([A_2B])`

`K_c=((2x)^2* (x))/((0.87-x))`

`K_c=(4x^3)/((0.87-x))`

Therefore, the equilibrium constant expression will be
`K_c=(4x^3)/((0.87-x))`