At a certain temperature,
Kc equals 1.40 × 10
2 M
-1 for the reaction:
2 CO(g) + O
2(g)

2 CO
2(g)
If a 3.00 L flask contains 0.400 mol of CO
2 and 0.100 mol of O
2 at equilibrium, how many moles of CO are also present in the flask?
◦ 0.555 mol
◦ 0.185 mol
◦ 0.107 mol
◦ 0.0114 mol