Matter is anything that has mass and volume.
Gases are matter.
Fluids more dense than the fluid they are in will sink.
8th grade - Physical Science
Structure of Matter
- Students know the states of matter (solid, liquid, gas) depend on molecular motion.
- Students know that in solids the atoms are closely locked in position and can only vibrate; in liquids the atoms and molecules are more loosely connected and can collide with and move past one another; and in gases the atoms and molecules are free to move independently, colliding frequently.
Do gases have mass?
Yes, gases are matter and have mass.
Gases like air are invisible therefore they don't have mass.
Photographs and Movies
Set-up for balance.