Final answer:
The equilibrium constant, Kc, for the given reaction can be calculated using the concentrations of the reactants and products at equilibrium.
Step-by-step explanation:
The equilibrium constant, Kc, is a measure of the extent to which a reaction has reached equilibrium. It is calculated using the concentrations of the reactants and products at equilibrium. In this case, the reaction is 2NOCI(g) + 2NO(g) + Cl2(g) <-> 2NOCl(g).
Given that 1.25 mol NOCl was placed in a 2.50 L reaction chamber at 427°C and after equilibrium was reached, 1.10 moles NOCl remained, we can calculate the equilibrium constant, Kc, using the formula:
Kc = [NOCl]^2 / ([NO]^2[Cl2])
Substituting the values into the equation, we get Kc = (1.10/2.50)^2 / ((1.25 - 1.10)/2.50)^2 = 0.44.
Therefore, the correct answer is A. Kc = 0.44.