Answer to Question #259434 in General Chemistry for Sisi

Question

a student performed an experiment to determine the molecular weight of a gaseous compound. Using the ideal gas law PV=nRT, and knowing the pressure, temperature and volume of the vapor the student calculated the number of moles of gas,n , to be .0443 mole. the weight of the gas was 1.42 gram. what is the molecular weight of this compound?

Answer 1

Moles of gas = 0.0443

Weight of the gas = 1.42 g

Moles = Weight of gas / Molecular weight of gas

0.0443 = 1.42 / Molecular weight

Molecular weight = 1.42 / 0.0443 = 32 g/mole

So molecular weight of gas is 32 g/mole.