A chemist has synthesized a greenish yellow gaseous compound of chlorine and oxygen and finds that its density is 7.71g/L at 36 degree C and 2.88 atm. The molecular formula of the compound will be
K = C + 273,15 K = 36 + 273,15 K = 309,15 K Now, using Clayperon's equation, we have: PV = nRT P = (m/Mol)RT/V P = dRT/Mol Mol = dRT/P And finally: Mol = (7,71 . 0,082 . 309,15)/2,88 Mol ~ 67,86 g/Mol Obs.: In fact, considering Mol(cl) = 35,5 and Mol(o) = 16, we can predict that the molecular formula of the compound is ClO2 (chlorine dioxide).