Consider the following reaction:
COCl₂(g) ⇌ CO(g) + Cl₂(g0
A reaction mixture initially contains 1.6 M COCl₂.Determine the equilibrium concentration of CO if K_c for the reaction at this temperature is 8.33 × 10^-4.Calculate this based on the assumption that the answer is negligible compared to 1.6.

Question

Quizplus · Accepted Answer

Let x be the change in concentration for CO and Cl2SO2. Then the equilibrium concentration of COCl2 is 1.6 - x.

The equilibrium constant expression is:

Kc = [CO][Cl2SO2] / [COCl2]

Substitute equilibrium concentrations and the value of Kc into the expression and solve for x:

8.33 × 10^-4 = (x)(x) / (1.6 - x)

Assuming that x is negligible compared to 1.6, we can simplify the equation and solve for x:

8.33 × 10^-4 = x^2 / 1.6

x^2 = 8.33 × 10^-4 * 1.6

x^2 = 1.3328 × 10^-3

x = 1.154 × 10^-2

The equilibrium concentration of CO is:

[CO] = x = 1.154 × 10^-2 M

The best choice is C because it is closest to 1.154 × 10^-2 M.

Consider the Following Reaction