Yes
helium is a gas less dense than air.
Yes solvents are heavier than air
Nitrous Oxide is heavier than air.
Helium is used to inflate balloons because it is lighter than air and that makes the balloon float.
Yes, argon is heavier than air. Argon has a higher density than air, so it will sink below the air in the atmosphere.
"Heavier than air" refers to airplanes.
An airplane is a heavier than air flying craft
Yes, LP gas is heavier than air.
Both are gases.
Gas is heavier than oxygen. Cold air is heavir than hot air
One is lighter and the other one is heavier. :D
they are heavier than air hence why they don't fly unless in motion.