For the reaction pcl5(g) 4 pcl3(g) 1 cl2(g) kp 5 23.6 at 500 k a. calculate the equilibrium partial pressures of the reactants and products at 500 k if the initial pressures are ppcl5 5 0.560 atm and ppcl3 5 0.500 atm.

= 42.9 atm, = 93.4 atm and = 7.66 atm

Explanation: The given balanced equation is:

Initial pressure of = 50.560 atm  

initial pressure of = 50.500 atm

Let's say the change in pressure is p. Then:

equilibrium partial pressure of = (50.560 - p) atm

equilibrium partial pressure of = (50.500 + p) atm

equilibrium partial pressure of = p atm

Let's plug in the values in it:

on cross multiply:

on rearranging the above equation:

It's a quadratic equation. On solving this equation:

p = 42.9

So, the equalibrium partial pressure of = 42.9 atm

equilibrium partial pressure of = 50.500 + 42.9 = 93.4 atm

equilibrium partial pressure of = 50.560 - 42.9 = 7.66 atm

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