Question

1)

Consider the reaction shown below. The concentration of NO2 (g) at equilibrium in a container at 25 oC is 0.100 M. Calculate the concentration of N2O4. For reference, Keq = 8.8 at 25 oC. Show your work.

Answer 1

You are not showing the reaction, so I'll assume basing on your data that the reaction is this:

2NO₂ <------> N₂O₄   K = 8.8

K = [N₂O₄] / [NO₂]² --> Solving for N₂O_4: [N₂O₄] = K [NO₂]²

[N₂O₄] = 8.8 * (0.1)²

[N₂O₄] = 0.088 M

Hope this helps

PS: If the reaction is not the one I wrote, but instead is the inverse reaction, all you have to do is inverse the expression for K, and then the expression will be : [N₂O₄] = [NO₂]² / K. Just substitute the value and you should get the result.