Usually helium unless you're blowing it up yourself, then it's carbon dioxide.
The gas commonly used in balloons is helium. It is lighter than air, which causes the balloon to float when it is filled with helium.
HELIUM
In balloons, it is desirable to use the lightest possible gas. Nitrogen is a relatively heavy gas with Atomic mass no. of 14. Instead, a much lighter gas, Helium, is used. It has an Atomic mass no. of 4. Hydrogen was used a long time ago, since it was the lightest gas. But due to its explosive nature, it is no longer used.
helium
Helium
Hydrogen is too flammable
Helium
Helium to get them to float.
Helium
Hot air is used for hot air balloons.
Helium
HELIUM
Helium is the safest gas to fill in balloons, as it is light and noncombustable.
Any gas- but if you want them to SAFELY float, use helium.
gas tank, plastic, wood
I think it is helium, I could be wrong.
If you want the balloons to float, you would probably use helium.
This gas is helium.