Which one among the following statements for the gases mentioned below is not correct?

  1. A. Hydrogen has 3 isotopes.
  2. B. Helium is a commonly used gas in electric bulbs.
  3. C. Oxygen is used to burn fuel in rocket engines in spacecraft.
  4. D. Nitrogen can be used in gaseous form to replace air in food packaging.

Correct Answer: B. Helium is a commonly used gas in electric bulbs.

Explanation

Argon or Nitrogen, not Helium, is commonly used in electric bulbs to prevent the filament from oxidizing[cite: 1].

Related questions on Chemistry

Practice more CDS General Knowledge questions