Nitrogen monoxide and oxygen can be formed from the thermal decomposition of nitrogen dioxide.2NO2 (g) = 2NO (g) + O₂(g)In an experiment, 4 moles of nitrogen dioxide were put into a 1.0 dm³ container and heatedto a constant temperature. The equilibrium mixture contains 0.8 moles of oxygen.What is the value of the equilibrium constant, Kc?

To find the equilibrium constant Kc, we first need to understand the reaction and the stoichiometry. The balanced chemical equation is:

2NO2 (g) ⇌ 2NO (g) + O2 (g)

From the problem, we know that we started with 4 moles of NO2, and at equilibrium we have 0.8 moles of O2.

Since the reaction is balanced with a 2:2:1 ratio, the change in moles of NO2 and NO is twice that of O2. Therefore, the change in moles of NO2 is -20.8 = -1.6 moles, and the change in moles of NO is +20.8 = +1.6 moles.

So, at equilibrium, we have:

[NO2] = 4 - 1.6 = 2.4 moles [NO] = 0 + 1.6 = 1.6 moles [O2] = 0.8 moles

Since these are in a 1.0 dm³ container, the concentrations at equilibrium are:

[NO2] = 2.4 mol/dm³ [NO] = 1.6 mol/dm³ [O2] = 0.8 mol/dm³

The expression for Kc is:

Kc = ([NO]^2 * [O2]) / [NO2]^2

Substituting the equilibrium concentrations into the Kc expression gives:

Kc = (1.6^2 * 0.8) / 2.4^2 = 0.64 mol/dm³

So, the equilibrium constant Kc for this reaction at this temperature is 0.64 mol/dm³.