Related questions


How do you calculate molar mass?

Suppose you received a sample of an unknown gas. The hard mass spectrum of the sample shows peaks at 19amu and 31amu in a 5 to one intensity ratio. You determine that it takes 3.99g of gas to fill an evacuated 750ml flask to a final pressure of 1.02 atm at 21.2 degrees Celsius. What is the empirical formula of the unknown gas? What are the molar mass and molecular formula of the gas?
b) To verify the result, you decide to determine the molar mass of the unknown gas independently based on the rate of effusion relative to that of Ne. You find that Ne effused at a rate of .37 mol per 37 seconds, and the unknown gas effused at a rate of .53mol per 2.2 minutes. calculate the molar mass of the unknown mass.