Thread: Atomic radii

I know that atomic radius decreases as we go across the period ( from left to right ) because of an increase in net nuclear charge, but in period 3 (Na --> Ar) the atomic radius of Ar , which is the last element of the period is larger than the rest of the elements in period 3....does anyone know why?

You have to ignore the noble gases because they don't form bonds. You would have to measure their van der Walls radius.

All the sources that I find say that Ar is the smallest, as expected.

http://www.creative-chemistry.org.uk...e1/trends5.htm