The value of the equilibrium constant for the gas-phase reaction
2 NOCl(g) ∏ 2 NO(g) + Cl₂(g)
Is K = 7.65 * 10^-8 at 298.15 K. Determine the value of the equilibrium constant expressed in terms of concentrations, K_c, at this temperature.

Question

Quizplus · Accepted Answer

The equilibrium constant expressed in terms of concentrations, K_c, is related to the equilibrium constant expressed in terms of partial pressures, K_p, by the following equation:K_c = K_p(RT)^Δnwhere R is the ideal gas constant, T is the temperature in Kelvin, and Δn is the change in the number of moles of gas in the reaction.In this case, Δn = 2 - 3 = -1, so:K_c = K_p(RT)^-1Substituting the given values into this equation, we get:K_c = (7.65 × 10^-8)(0.0821)(298.15)^-1 = 3.10 × 10^-9

The Value of the Equilibrium Constant for the Gas-Phase Reaction