PLS HELP I REALLY NEED IT IM ON THE VERGE OF TEARS
How many liters of O2 at STP will react with 8.7 grams of C2H4 to form CO2 and H2O?

C2H4 + 3 O2 -------> 2 CO2 + 2 H2O
the answers could be
22
21
2.3
I though the answer would be 26.1 PLSPLSPLS HELP