At a certain temperature, 13.0 moles of SO3 are placed into a rigid 2.0 L container.
The SO3 dissociates as follows:
2 SO3 (g) ⇌ 2 SO2 (g) + O2 (g)
At equilibrium 10 moles of SO3 are present.
Calculate Keq at this temperature.
I got that K=[SO2]^2*[O2]^1/[SO3]^2
but that's all I have