Question

Which element is more reactive? *
Cs
Rb

Answer 1

Rb is more reactive .

Rubidium is the second most reactive metal and is very soft, with a silvery-white lustre.

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Answer 2

Rubidium is a typical but very reactive member of the series of alkali metals. It is appreciably more reactive than potassium, but less so than caesium, and so would be expected to react more violently with those materials that are hazardous with potassium or sodium.