Rubidium ground state electronic configuration

Silver and rubidium both form +1 ions, but silver is far less reactive. Suggest an explanation, taking into account the ground-state electron configurations of these elements and atomic radiL... 

The alkali metals - lithium, sodium, potassium, rubidium, caesium and francium - are members of group 1 of the periodic table, and each has a ground state valence electronic configuration ns. Discussions of these metals usually neglect the heaviest member of the group, francium. Only artificial isotopes of francium are known, the longest Uved, Fr, having n = 21.8 min. 

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