Concept:Identifying the false statement among given facts about gases.
Explanation:The question asks which statement is not correct.
Statement A: Hydrogen has three isotopes: protium (
1H), deuterium (
2H), and tritium (
3H).
This is correct.
Statement B: Helium is commonly used in electric bulbs.
This is false. The common filling gas in incandescent bulbs is argon, not helium.
Argon is inert and prevents the tungsten filament from oxidizing.
Helium is used in balloons, airships, and cooling applications, not in electric bulbs.
Statement C: Oxygen is used to burn fuel in rocket engines in spacecraft.
This is correct. Liquid oxygen (LOX) serves as an oxidizer for combustion in the vacuum of space.
Statement D: Nitrogen can be used in gaseous form to replace air in food packaging.
This is correct. Nitrogen is inert and used in modified atmosphere packaging (MAP) to reduce spoilage.
Thus, only statement B is incorrect.
Answer:B. Helium is a commonly used gas in electric bulbs. (This statement is not correct.)