What is Kc for the following equilibrium when the equilibrium concentration of each substance is: [SO2]= 0.60M, [O2] = 0.82M and [SO3] = 1.90M?

2SO2(g) + O2(g) ⇌2SO3(g)

The equilibrium constant Kc is the ratio of product of concentration of Product raise to their coefficients and product of concentration of reactants raised to their coefficients in balanced chemical equation.

i.e., For a chemical change,


aA + bB ⇌ cC + dD


Equilibrium constant Kc for the reaction,



For given reaction,


2SO2(g) + O2(g) ⇌2SO3(g)


Equilibrium constant,


Given that, Equilibrium concentrations of each substance are,


[SO2] = 0.60M = 0.60 mol litre-1


[O2] = 0.82M =0.82 mol litre-1


[SO3] = 1.90M = 1.90 mol litre-1


Thus,


Kc =


⇒ Kc = 12.299 M-1


Or Kc = 12.299 L mol-1


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