Question

A 2.5 L flask is filled with 0.25 atm SO3, 0.20 atm SO2, and 0.40 atm O2, and allowed to reach equilibrium. Assume at the temperature of the mixture is chosen so that Kp = 0.12. Predict the effect on the partial pressure of SO3 as equilibrium is achieved by using Q, the reaction quotient.

Answer 1

Explanation:

Reaction equation for the given chemical reaction is as follows.

      $2SO_{3} \rightleftharpoons 2SO_{2} + O_{2}$

Equation for reaction quotient is as follows.

         Q = $\frac{P^{2}_{SO_{2}} \times P_{O_{2}}}{P^{2}_{SO_{3}}}$

             = $\frac{(0.20)^{2} \times 0.40}{(0.25)^{2}}$

             = 0.256

As, Q > K (= 0.12)

The effect on the partial pressure of $SO_{3}$ as equilibrium is achieved by using Q, is as follows.

• This means that there are too much products.

• Equilibrium will shift to the left towards reactants.

• More $SO_{3}$ is formed.

• Partial pressure of $SO_{3}$ increases.