For a given Period, which is the smallest atom?
The inert gases are in fact the SMALLEST atoms of their respective Periods.
Do these data support the opening statement?
And as we face the Table, atomic size DECREASES across the Period from right to left, and INCREASES down a Group, a column of the Periodic Table.
The Periodic decrease is a consequence of electronic structure. Incomplete electron shells shield the nuclear charge very ineffectively. Across the Period,