Imagine that you have a 5.00L gas tank and a 3.50L gas tank. You need to fill one tank with oxygen and the other with acetylene to use in conjunction with your welding torch. If you fill the larger tank with oxygen to a pressure of 145atm , to what pressure should you fill the acetylene tank to ensure that you run out of each gas at the same time? Assume ideal behavior for all gases.

Question

Imagine that you have a 5.00L  gas tank and a 3.50L  gas tank. You need to fill one tank with oxygen and the other with acetylene to use in conjunction with your welding torch. If you fill the larger tank with oxygen to a pressure of 145atm , to what pressure should you fill the acetylene tank to ensure that you run out of each gas at the same time? Assume ideal behavior for all gases.

DrBob222 · Answer

2C2H2 + 5O2 ==> 4CO2 + 2H2O For the large tank, n = PV/RT Solve for n = # moles O2 Convert mols O2 to moles C2H2 and use PV = nRT and solve for P. I get a little over 500 atm.