Exactly 1.0 mol N2O4 is placed in an empty 1.0-L container and is allowed to reach equilibrium described by the equation N2O4(g) 2NO2(g) If at equilibrium the N2O4 is 39% dissociated, what is the value of the equilibrium constant, Kc, for the reaction under these conditions

Respuesta :

Answer: The value of equilibrium constant is 0.997

Explanation:

We are given:

Percent degree of dissociation = 39 %

Degree of dissociation, [tex]\alpha[/tex] = 0.39

Concentration of [tex]N_2O_4[/tex], c = [tex]\frac{1mol}{1L}=1M[/tex]

The given chemical equation follows:

                     [tex]N_2O_4\rightleftharpoons 2NO_2[/tex]

Initial:                c             -

At Eqllm:         [tex]c-c\alpha[/tex]      [tex]2c\alpha[/tex]

So, equilibrium concentration of [tex]N_2O_4=c-c\alpha =[1-(1\times 0.39)]=0.61M[/tex]

Equilibrium concentration of [tex]NO_2=2c\alpha =[2\times 1\times 0.39]=0.78M[/tex]

The expression of [tex]K_{c}[/tex] for above equation follows:

[tex]K_{c}=\frac{[NO_2]^2}{[N_2O_4]}[/tex]

Putting values in above equation, we get:

[tex]K_{c}=\frac{(0.78)^2}{0.61}\\\\K_{c}=0.997[/tex]

Hence, the value of equilibrium constant is 0.997