Multiple choice

Balloons are filled with

  1. helium

  2. oxygen

  3. nitrogen

  4. argon
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Helium is used to fill balloons because it's lighter than air and non-flammable, unlike hydrogen which is also light but extremely dangerous. Helium is a noble gas that doesn't react with other substances. Being the second lightest element after hydrogen, it provides the lift needed for balloons and airships while remaining completely safe.

Keep practicing — related questions