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Most reactive metal and nonmetal, why?
What is Francium (metal) Fluorine (nonmetal). Francium only needs to give up one valence electron, and with all of it's electron orbitals, it is a distance from the nucleus, so there isn't a strong hold on it. For Fluorine, it only needs one valence electron, and has only 2 orbitals, so it has a strong attraction for them.