At 2000°C, the equilibrium constant for the reaction below is Kc = 4.10 ´ 10–4 . If 0.600 moles of NO is placed in a 1.0-L reaction vessel, what will the equilibrium concentration of N2 be?

Respuesta :

Answer:

At equilibrium, the concentration of [tex]N_{2 (g)}[/tex] is going to be 0.30M

Explanation:

We first need the reaction.

With the information given we can assume that is:

[tex]N_{2 (g)}[/tex] + [tex]O_{2 (g)}[/tex] ⇄ 2[tex]NO_{(g)}[/tex]

If there is placed 0.600 moles of NO in a 1.0-L vessel, we have a initial concentration of 0.60 M NO; and no [tex]N_{2 (g)}[/tex] nor  [tex]O_{2 (g)}[/tex] present. Immediately, [tex]N_{2 (g)}[/tex] and[tex]O_{2 (g)}[/tex] are going to be produced until equilibrium is reached.

By the ICE (initial, change, equilibrium) analysis:

I: [[tex]N_{2 (g)}[/tex]]=0   ;     [[tex]O_{2 (g)}[/tex] ]= 0    ; [[tex]NO_{(g)}[/tex]]=0.60M

C: [[tex]N_{2 (g)}[/tex]]=+x   ;     [[tex]O_{2 (g)}[/tex] ]= +x    ; [[tex]NO_{(g)}[/tex]]=-2x

E: [[tex]N_{2 (g)}[/tex]]=0+x   ;     [[tex]O_{2 (g)}[/tex] ]= 0+x   ; [[tex]NO_{(g)}[/tex]]=0.60-2x

Now we can use the constant information:

[tex]K_{c}=\frac{[products]^{stoichiometric coefficient} }{[reactants]^{stoichiometric coefficient} }[/tex]

[tex]4.10* 10^{-4} =\frac{(0.60-2x)^{2}}{(x)*(x)}[/tex]

[tex]4.10* 10^{-4}[/tex]= [tex]\frac{(0.60-2x)^{2}}{x^{2} }[/tex]

[tex]4.10* 10^{-4} * x^{2}[/tex]= [tex](0.60-2x)^{2}}[/tex]

[tex]\sqrt{4.10* 10^{-4} * x^{2}}[/tex]= [tex]\sqrt{(0.60-2x)^{2}}}[/tex]

[tex]0.0202 x =0.60 - 2x[/tex]

[tex]2x+0.0202x=0.60[/tex]

[tex]x=\frac{0.60}{2.0202}[/tex][tex]= 0.30[/tex]

At equilibrium, the concentration of [tex]N_{2 (g)}[/tex] is going to be 0.30M