What is the concentration of each gas once equilibrium is reached?

Question

Can someone please let me know if I did this right? 

 

1.800 mole of N₂O₄(g) is injected into a closed 1.00L container.

K_c=4.66 x 10^-3 at 298K

 

N₂O₄ (g) ⇌ 2NO₂ (g)

 

what is the concentration of each gas once equilibrium is reached?

 

I set up an ICE table as follows:

 

I  1.80         0

C  -x           +2x

E  1.80-x     2x

 

then input the values from row E into K_c equation:

 

4.66 x 10^-3= (2x)²

                  (1.80-x)

 

using the quadratic equation I found x= 0.0452, and x= -0.0463

 

using the positive value for x to find the concentrations of each gas at equilibrium, I found:

[N₂O₄]= 1.80-x

             1.80-0.0452

              1.75M

 

[NO₂]= 2x

            2(0.0452)

            0.0904M

          

 

 

Answer 1

Yes.  You did do this correctly.

NOTE:  I didn't check the math but the approach is spot-on.

Answer 2

You did this correctly &^ I checked your work.