At a particular temperature, K = 2.0 10-6 mol/L for the following reaction.

Question

2 CO2(g) 2 CO(g) + O2(g)

If 1.8 mol CO2 is initially placed into a 5.9-L vessel, calculate the equilibrium concentrations of all species.

Answer 1

You need to learn where the arrow keys are and USE them.
...........2CO2 ==> 2CO + O2
initial....1.8........0....0
change.....-2x......2x.....x
equi.....1.8-2x.....2x.....x

Substitute the equil concns from the ICE chart into the Kc expression and solve for x. Then evaluate each element/compound. PLEASE note that x = moles. You must divide each by 5.9L to obtain concn in molarity.
Also note that you can sart by 1.8mol/5.9L = ?M and use M through out the ICE chart in which case x will be in molarity.