Why is helium used in blimps instead of hydrogen?

• A. Helium is more abundant in Earth's atmosphere than hydrogen.
• B. Helium reacts with air to form a stable compound.
• C. Helium is non-flammable, making it safer than hydrogen.
• D. Helium is heavier than hydrogen, providing more lift.

Answer: (C)

Verified step by step guidance

1. Understand the key property required for a gas used in blimps: it must be lighter than air to provide lift.
2. Recognize that hydrogen and helium are both lighter than air, so both can provide lift for blimps.
3. Consider the safety aspect: hydrogen is highly flammable and can easily ignite, posing a significant risk.
4. Helium, on the other hand, is a noble gas and is chemically inert, meaning it does not react or catch fire.
5. Therefore, helium is preferred over hydrogen in blimps because its non-flammable nature makes it much safer to use.