The given question is incomplete. The complete question is as follows.
Calculate the pressures of NO,
, and NOCl in an equilibrium mixture produced by the reaction of a starting mixture with 8.2 atm NO and 4.1 atm
. (Hint: KP is small; assume the reverse reaction goes to completion then comes back to equilibrium.)

Explanation:
According to the ICE table,
Initial: 8.2 4.1 0
Change: -4.1x -x +4.1x
Equilbm: (8.2 - 4.1x) (4.1 - x) +4.1x
Now, expression for
of the reaction is as follows.
![K_{P} = \frac{[NOCl]^{2}}{[NO]^{2}[Cl_{2}]}](https://tex.z-dn.net/?f=K_%7BP%7D%20%3D%20%5Cfrac%7B%5BNOCl%5D%5E%7B2%7D%7D%7B%5BNO%5D%5E%7B2%7D%5BCl_%7B2%7D%5D%7D)

x = 1.9
Therefore, at equilibrium
[NOCl] =
= 3.8
[NO] = (8.2 - 7.79) = 0.41
= 2 - 1.9 = 0.1