posted by Amy .
A compound has the empirical formula CHCL .A flask with volume 253 cm3 at temperature of 373K and pressure of 1.0 atm contains 0.8 g of the gaseous compound. Find the molecular formula of the compound.
Use PV = nRT and solve for n = number of mols.
Then n = grams/molar mass. You know n and grams, solve for molar mass.