Question

As an EPA scientist studying catalytic converters and urban smog, you want to find Kc for the following reaction: 2 NO2 (g) ⇋ N2(g) + 2 O2(g) Kc = ?? Use the following data to find the unknown Kc:
1/2 N2 (g) + 1/2 O2 (g) ⇋ NO (g) Kc = 0.004
2NO2 (g) ⇋ 2NO (g) + O2 (g) Kc = 0.056

Answer 1

Answer:

3500

Explanation:

The equilibrium constant of the reaction which has to be calculated is:-

2 NO2 (g) ⇋ N2(g) + 2 O2(g)

The given chemical equation follows:

1/2 N2 (g) + 1/2 O2 (g) ⇋ NO (g)

The equilibrium constant for the above equation is 0.004.

We need to calculate the equilibrium constant for the reverse equation of above chemical equation and also double of the above chemical equation, which is:

2NO (g) ⇋ N2 (g) + O2 (g)

The equilibrium constant for the reverse double reaction will be the reciprocal of the initial reaction.

If the equation is multiplied by a factor of '2', the equilibrium constant of the reverse reaction will be the square of the equilibrium constant  of initial reaction.

The value of equilibrium constant for reverse reaction is:

$K_{eq}'=(\frac{1}{0.004})^2$  = 62500

The given chemical equation follows:

2NO2 (g) ⇋ 2NO (g) + O2 (g)

The equilibrium constant for the above equation is 0.056.

Thus, adding the both reaction gives the original reaction. So, equilibrium constant is:- 62500 x 0.056 = 3500