First find the molar mass (mm) for Methane--> CH4 = 12+(1×4) = 16 grams/mole CH4 --> now flip this: So the = # of moles (n) = 12.5g CH4 × 1 mole CH4 / 16g CH4 n = 0.78 moles P = 1.30 atm, T = 40C = 273K + 40C = 313K, V = ?? PV = nRT --> V = nRT/P V = (0.78)(.082)(313) / 1.30 V = 20.1 / 1.30 = 15.4 L
