The equilibrium constant Kc for the following reaction is 2.18 ✕ 106 at 730°C. H2(g) + Br2(g) equilibrium reaction arrow 2 HBr(g) Starting with 2.50 moles of HBr in a 12.0 L reaction vessel, calculate the concentrations of H2, Br2, and HBr at equilibrium.

Respuesta :

Answer:

Equilibrium concentration of [tex][HBr]=0.2080 M[/tex]

Equilibrium concentration of [tex][H_2]=[Br_2]=0.0001408 M[/tex]

Explanation:

                [tex]H_2(g)+Br_2(g)\rightleftharpoons 2HBr(g)[/tex]..[1]

The equilibrium constant of reaction [1] =[tex]K_c=2.18\times 10^6[/tex]

Initial moles of HBr = 2.50 mol

Volume of the container = 12. 0 L

Concentration of a substance is calculated by:

[tex]\text{Concentration}=\frac{\text{Number of moles}}{\text{Volume}}[/tex]

So, concentration of methane = [tex]\frac{0.0410}{1.00}=0.0410M[/tex]

Concentration of HBr = [tex]\frac{2.50 mol}{12.0 L}=0.2083 M[/tex]

The given chemical equation follows:

                   [tex]2HBr(g)\rightleftharpoons H_2(g)+Br_2(g)[/tex]

Initial:          0.2083 M

At eqllm:    (0.2083  - 2x)M                     x       x

The equilibrium constant of reaction [2] :

=[tex]K_c'=\frac{1}{K_c}=\frac{1}{2.18\times 10^6}=4.587\times 10^{-7}[/tex]

Evaluating the value of 'x', we get:

[tex]K_c'=\frac{[H_2][Br_2]}{[HBr]^2}[/tex]

[tex]4.587\times 10^{-7}=\frac{x\times x}{(0.2083 - 2x)^2}[/tex]

Solving for x:

x = 0.0001408

Equilibrium concentration of [tex][HBr]=(0.2083-2x)M =0.2080 M[/tex]

Equilibrium concentration of [tex][H_2]=[Br_2]=x =0.0001408 M[/tex]