Helium is used in balloons because?

Answer:
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.
First answer by Stormish. Last edit by Stormish. Contributor trust: 533 [recommend contributor recommended]. Question popularity: 1 [recommend question].