Chapter 8, Problem 8.38QP

Interpretation Introduction

Interpretation: The atoms, $Na$, $Al$, $P$, $Cl$ and $Mg$ has to be arranged in the order of decreasing radii.

Concept Introduction:

Atomic radius is the distance between the atomic nucleus and outermost shell having electrons of an atom. From the atomic radius, the size of atoms can be visualized

Along the period, the valence electron is added to the same shell and thus attraction by the nucleus gets stronger. Therefore, atomic radii reduces from left to right in the periodic table, atomic radii increases from top to bottom in the periodic table.