Which one of the following is NOT radioactive?
- AAstatine
- BFrancium
- CTritium
- DZirconiumCorrect
Explanation
Zirconium is the correct answer because it is a stable transition metal. Unlike the other options, its naturally occurring isotopes are stable and do not undergo radioactive decay.
Astatine is a highly unstable radioactive element and is the rarest naturally occurring element in the Earths crust.
Francium is an extremely radioactive alkali metal with a very short half life.
Tritium is a radioactive isotope of hydrogen.
Therefore, Zirconium is the only element among the choices that is not classified as radioactive.
Related questions
More UPSC Prelims practice from the same subject and topic.
- Prelims 2001GS1science-and-technology
The theme of Indian Science Congress, 2001 was
- Prelims 2001GS1science-and-technology
Match List I with List II and select the correct answer using the codes given below the Lists: List I List II (Institute) (Location) I. Central Institute of Medicinal and Aromatic Plants A) Chandigarh…
- Prelims 2001GS1science-and-technology
Two wires have their lengths, diameters and resistivities, all in the ratio of 1: 2. If the resistance of the thinner wire is 10 ohms, the resistance of the thicker wire is
- Prelims 2001GS1science-and-technology
Assertion (A): A stick is dipped in water in a slanting position. If observed sideways, the stick appears short and bent at the surface of water. Reason (R): The light coming from the stick undergoes …
- Prelims 2001GS1science-and-technology
When light waves pass from air to glass, the variables affected are
- Prelims 2001GS1science-and-technology
When water is heated from 0°C to 10°C, its volume