What is the name of the 87th element on the periodic table that has no known biological cole because it has a half-life of only 22 minutes?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. Francium.
Francium (Fr), the 87th element on the periodic table, is a highly radioactive alkali metal with a very short half-life, making it too unstable for any known biological role. Its most stable isotope, Francium-223, has a half-life of only 22 minutes.
Other Options:
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Meitnerium (Mt, Element 109): A synthetic element with an extremely short half-life (seconds), not naturally occurring.
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Dubnium (Db, Element 105): Another synthetic element with no biological significance due to its fleeting existence.
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Seaborgium (Sg, Element 106): A man-made element with a half-life of mere seconds, irrelevant biologically.
Francium, despite being natural, decays too quickly to participate in biological processes, unlike stable alkali metals like sodium or potassium. Its rarity and radioactivity make it purely of scientific interest.