The question is incomplete, here is the complete question:
Phosgene,
, gained notoriety as a chemical weapon in World War I. Phosgene is produced by the reaction of carbon monoxide with chlorine:

The value of
for this reaction is 5.79 at 570 K. What are the equilibrium partial pressures of the three gases if a reaction vessel initially contains a mixture of the reactants in which
and
?
<u>Answer:</u> The equilibrium partial pressure of CO,
is 0.257 atm, 0.257 atm and 0.008 atm respectively.
<u>Explanation:</u>
The relation of
is given by:

= Equilibrium constant in terms of partial pressure
= Equilibrium constant in terms of concentration = 5.79
= Difference between gaseous moles on product side and reactant side = 
R = Gas constant = 
T = Temperature = 570 K
Putting values in above equation, we get:

We are given:
Initial partial pressure of CO = 0.265 atm
Initial partial pressure of chlorine gas = 0.265 atm
Initial partial pressure of phosgene = 0.00 atm
The given chemical equation follows:

<u>Initial:</u> 0.265 0.265
<u>At eqllm:</u> 0.265-x 0.265-x x
The expression of
for above equation follows:

Putting values in above equation, we get:

Neglecting the value of x = 8.59 because equilibrium partial pressure cannot be greater than initial pressure
So, the equilibrium partial pressure of CO = 
The equilibrium partial pressure of 
The equilibrium partial pressure of 
Hence, the equilibrium partial pressure of CO,
is 0.257 atm, 0.257 atm and 0.008 atm respectively.