At a certain temperature, the equilibrium constant, 𝐾, for the given reaction is 53.3. H2(g)+I2(g)↽−−⇀2HI(g)𝐾=53.3

Question

At this temperature, the reactants were placed in a container to react. If the partial pressures of H2 and I2 were each 0.500 bar initially, what is the partial pressure of HI at equilibrium?

𝑃HI=bar?

Answer 1

Because the reaction involves only gases, remember the equilibrium expression is similar to when the reactants are in solution.

This expression would be K_p = (P_HI)² / (P_H2) (P_I2) = 53.3

You will need to plug the necessary information in and solve for the P_HI .

x² / (0.500)² = 53.3 ; x= P_HI = 3.65