What volume of oxygen at STP is required to affect the combustion of 11 liters of ethylene (C2H4) at 273 degree celsius and 380 mm Hg pressure?
C2H4+3O2→2CO2+2H2O
The ratio of ethylene to oxygen is 1:3.
Therefore 3 times the amount of acetylene is required to affect the combustion of ethylene.
I.e. 33 L of oxygen.