Are elements such as Plutonium and Uranium more reactive than Francium?

Answer 1

It's important to note that plutonium and uranium (element names are not normally capitalized in the middle of a sentence) have isotopes which are stable enough that their reactivity is experimentally known, while the most stable isotope of francium has a half-life of about 20 minutes. Francium's reactivity is therefore partially a matter of conjecture... the energy given off by its radioactive decay would literally vaporize any reasonably sized piece.

That said, as an alkali metal francium would be much more reactive than uranium or plutonium, both of which are transition metals.

Answer 2

No, Francium is the most reactive element in the Periodic Table due to its low ionization energy, which means it readily gives away electrons. Plutonium and Uranium are not as reactive as Francium, as they typically undergo radioactive decay rather than chemical reactions.