In general, ionic radius decreases with increasing positive charge. As the charge on the ion becomes more positive, there are fewer electrons. The ion has a smaller radius. In general, ionic radius increases with increasing negative charge.
Furthermore, are isoelectronic ions the same size?
An Isoelectronic Series is a group of atoms/ions that have the same number of electrons. A typical question about isoelectronic series usually involve size comparisons. Since the number of electrons are the same, size is determined by the number of protons.
What is the trend of ion size?
The Periodic Trend. Due to each atom's unique ability to lose or gain an electron, periodic trends in ionic radii are not as ubiquitous as trends in atomic radii across the periodic table. Therefore, trends must be isolated to specific groups and considered for either cations or anions.