Question

what do u mean by atomic size?​

Answer 1

The atomic radius of a chemical element is a measure of the size of its atoms. It represents the mean distance from the nucleus to the boundary of the surrounding cloud of electrons. ... Radii generally decrease along each period (row) of the table from left to right and increase down each group (column).

Answer 2

Atomic size is the distance between the centre of the nucleus of an atom and its outermost shell. In basic chemistry, the atomic radius is defined as the shortest distance between the atom's nuclei and the outermost shell of the atom.