MHT CET · Chemistry · d and f Block Elements
Which element from following is radioactive?
- A Pr
- B Nd
- C Pm
- D Sm
Answer & Solution
Correct Answer
(C) Pm
Step-by-step Solution
Detailed explanation
Promethium is a chemical element with the symbol \(\mathrm{Pm}\) and atomic number 61. All of its isotopes are radioactive; it is extremely rare, with only about 500-600 grams naturally occurring in Earth's crust at any given time.
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