A mixture of propane and methane occupied 122 mL at 25 degree celsius and 1.0 atm. This mixture was burned in excess O2 to produce CO2(g) and H2O(g). The mass of the CO2 produced was 0.506 g. What is...

A mixture of propane and methane occupied 122 mL at 25 degree celsius and 1.0 atm. This mixture was burned in excess O2 to produce CO2(g) and H2O(g). The mass of the CO2 produced was 0.506 g. What is the ass% composition of the original mixture? Show all work.