# Please help?

Please answer the question it's very urgent.. Thanks!

See the photo

### 1 Answer

- hcbiochemLv 73 months ago
Kp = PA2(PB2)/(PAB)^2 = 1X10^-4

Set up an ICE table:

........................PAB.........PA2............PB2

Initial.................8.............0.................0

Change..........-2x............+x...............+x

Final.............8-2x.............x.................x

Kp = (x)(x)/(8-2x)^2 = 1X10^-4

The best first step in solving this is to take the square root of both sides to give

x/(8-2x) = 1X10^-4

x = 8X10^-4 - 2x10^-4x

1.0002x = 8X10^-4

x = 8X10^-4 = PA2 = PB2

PAB = 7.998

None of the given answers is actually correct. It looks like the value of K in the question was changed without changing the answers. Since the pressure of AB in the problem is given with only one significant figure, the correct final pressure of AB would actually be reported as 8 atm.