) Dinitrogen Tetroxide partially decomposes according to the following equilibrium: N2O4 (g) 2NO2 (g) A 1.00-L flask is charged with 0.400 mol of N2O4. At equilibrium at 373 K, 0.0055 mol of N2O4 remains. Keq for this reaction is __________.

Respuesta :

Answer: The value of [tex]K_{eq}[/tex] for this reaction is 1.578.

Explanation:

Given: Initial moles of [tex]N_{2}O_{4}[/tex] = 0.4 mol

Volume = 1.00 L

Therefore, initial concentration of [tex]N_{2}O_{4}[/tex] is calculated as follows.

[tex]Concentration = \frac{moles}{volume}\\= \frac{0.4}{1.0 L} mol\\= 0.4 M[/tex]

Now, ICE table for the given reaction equation is as follows.

                     [tex]N_{2}O_{4}(g) \rightleftharpoons 2NO_{2}[/tex]

Initial:               0.4               0

Change:           -x                +2x

Equib:  0.4 - x = 0.0055       2x

Hence, the value of x is calculated as follows.

0.4 - x = 0.0055

x = 0.4 - 0.0055

= 0.3945

Now, the [tex][NO_{2}][/tex] is calculated as follows.

2x = [tex][NO_{2}][/tex] = [tex]2 \times 0.3945 = 0.789[/tex]

Therefore, [tex]K_{eq}[/tex] for the given reaction is calculated as follows.

[tex]K_{eq} = \frac{[NO_{2}]^{2}}{[N_{2}O_{4}]}\\= \frac{(0.789)^{2}}{(0.3945)}\\= 1.578[/tex]

Thus, we can conclude that [tex]K_{eq}[/tex] for this reaction is 1.578.