helium
Hydrogen is too flammable
Helium is used in balloons because it is much less dense than air, allowing the balloons to float and is completely nontoxic and nonflammable unlike hydrogen, which is otherwise a superior lifting gas.
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.
Hydrogen was one of the earliest gases to be used for inflatable flying balloons, but following the Hindenberg disaster helium is now used, as it is chemically inert.
Helium.
Foil balloons are filled with helium. Helium is lighter than air and because of this, it is one of the gases that can make a balloon float. It's the preferred gas for these type of balloons because it isn't flammable and is inert, meaning undesired chemical reactions are rare.
helium
either for balloons, or whip it's.
Helium is a gas used to inflate lighter than air balloons.
Hot air is used for hot air balloons.
Helium
Helium.
to keep the balloon floating
helium
helium
helium