Question

11) Which of the following noble gases cannot be used up for filling electric bulbs

• A. helium
• B. Neon
• C. argon
• D. radon

Answer 1

The correct option is D

radon

Explanation of the correct option:

To slow down the sublimation process of tungsten, we use noble gases for filling in electric bulbs because they are inert and they do not react with any of the chemical species.

(D) Radon is radioactive element which is formed on the decay of uranium and is used in treatment of cancer, hence it is not used in electric bulbs.

Explanation for the incorrect options:

(A) Helium is readily used in electric bulbs.

(B) Neon is used for filling in electric bulbs because it is non -reactive gas.

(C) Argon is mostly used in electric bulbs for filling as it is a noble gas and is non - reactive.

Hence, the correct option is (D).