If you are given 7.34moles of a gas at 540K and a pressure of 2.3atm, what is the volume of the gas?

140 L (141.409 without rounding)

Explanation:

Assuming ideal behavior (so that we can use the ideal gas law), we can plug into the equation PV=nRT.  P=2.3 atm, n=7.34 mol, and T=540 K.  (If converting from Celsius to Kelvin, add 273.15.) For R, we'll use 0.082057 L*atm/(mol*K) so that the units cancel out.  2.3 atm*V=7.34 mol*.082057 Latm/(molK)*540 K.  Divide both sides by 2.3 to get the Volume in liters.  That will give you a volume of 140 L (with sig figs.  If you don't round it, you'd get 141.409 L).

3 hours because it is a decent distance.