Question

Acetylene torches are used for welding. These torches use a mixtureof acetylene gas, \rm C_2H_2, and oxygen gas, \rm O_2 to producethe following combustion reaction:

\rm 2C_2H_2{\it (g)} + 5O_2{\it (g)} \rightarrow 4CO_2{\it (g)} +2H_2O{\it (g)}
Imagine that you have a 5.50 L gas tank and a 4.50 L gas tank. Youneed to fill one tank with oxygen and the other with acetylene touse in conjunction with your welding torch. If you fill the largertank with oxygen to a pressure of 135 atm, to what pressure shouldyou fill the acetylene tank to ensure that you run out of each gasat the same time? Assume ideal behavior for all gases.
Express your answer with the appropriate units.