Question

At 1000 K, a sample of pure NO2 gas decomposes. 2 NO2(g) equilibrium reaction arrow 2 NO(g) + O2(g) The equilibrium constant KP is 158. Analysis shows that the partial pressure of O2 is 0.99 atm at equilibrium. Calculate the pressure of NO and NO2 in the mixture.

Answer 1

0.1575 atm

Step-by-step explanation:

we have that equilibrium constant Kp = (PNO)₂PO₂ / (PNO₂)₂

and it is given to be 158

==> Kp = (PNO)₂PO₂ / (PNO₂)₂ = 158

we also have that the partial pressure of O2 (PO₂) = 0.99 atm

Therefore,

PO₂ = 0.99 atm ==> PNO = 2(0.99 atm) = 1.98 atm (based on the stoichiometry)

==> PNO₂ = √((PNO)₂PO₂ / 158) atm = √((1.98)*2(0.99) / 158) atm = 0.1575 atm