Question: What is an atomic radius?

Fiona Fotherby answered on 31 Mar 2022:

Atom radius is the distance from the centre of an atoms nucleus, to the outer most electrons. It is more like the most probable distance, because electrons move around the nucleus, in orbital that have different shapes, depending on their hybridisation (elemental dependant).
So essentially it is the best estimate for size we have of a single atom! It is measured in angstrom usually (Å). There are 10000000 Å in 1 mm (one angstrom is 0.1 nm). A typically atomic radius is on the scale of about 3 angstrom. I hope this answers your question!