Question

The equilibrium constant is equal to 5.00 at 1300K for the reaction
2SO2(g) + O2(g) <--> 2SO3(g)
if initial concentrations are
[SO2] = 6.00M, [O2] = 0.45M,
[SO3]= 9.00M, the system is

a/. At equilibrium
b/. Not at equilibrium and will remain in an un equilibrated state
c/. Not at equilibrium and will shift to the left to achieve an equilibrium state
d/. Not at equilibrium and will shift to the right to achieve an equilibrim state.

Answer 1

Since you quote concentrations I assume the K of 5.00 is Kc.
Then
Kc = 5.00 = (SO3)^2/(SO2)^2(O2)
Qc = (9.00)^2/(6.00)^2(0.45) = 5.00

Since Qc = Kc, the system is in equilibrium.