Question

What element has the largest radius?

Answer 1

Got a Periodic Table.............?

Explanation:

Atomic size INCREASES ACROSS a Period from left to right as we face the Table, and INCREASES DOWN a Group. And thus the largest atomic radius should be exhibited by the alkali metal, francium, or perhaps by lanthanum or actinium.

But as chemists, as physical scientists, we should seek out some `"noombers"` to inform our argument. This site gives the atomic radius of francium as `1*stackrel*A` where `1*stackrel*A-=1xx10^-10*m`, which is a HUGE atomic radius.....and approaches actual bond lengths.........