Petra and Huy are doing a class demonstration to show that solids, liquids, and gases all have mass. They use a balance for the solids and the liquids. They wondered if gases have mass.



Which is the best way for them to show that air has mass?

Use a fan to make a current of air.


Compare the masses of two inflated balloons.


Heat water to show it changing to water vapor.


Compare the masses of an inflated and empty balloon.