C6H12 (g) + 9 O2 (g) ----> 6CO2 (g) + 6 H2O(g)

Question

How many L of oxygen gas is needed if we produce 5.66 L of CO2?

Answer 1

With all gases one can use volume in L directly as mols as a short cut.
5.66 L CO2 x (9 O2/6 CO2) = ?

Answer 2

3.77 L of o2