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What is the principal quantum number () of the valence shell for the alkali metal that is formed as s Block Elements Chemistry Question

Question

What is the principal quantum number ($n$) of the valence shell for the alkali metal that is formed as a radioactive decay product and has an extremely short half-life?

Answer: 7

💡 Solution & Explanation

Francium ($Fr$) is the radioactive alkali metal. Its general electronic configuration is $[Rn]7s^1$, meaning the principal quantum number of its valence shell is 7.

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