In this case there are a few different periodic trends at play. XX you XXXX XX the periodic table, moving XXXX a row will add a shell to the atom (XXXXXXX XXXXXX). XXXXXXX, moving XX the XXXXX XXXXX XXX atom XX XXXXXXX XXXXXXX. When you XXXX to the XXXXX, in a row, XXX XXXXXXX XXXX more XXX more XXXXXXXX, pulling the XXXXX ofelectrons closer to the XXXXXX (XXXXXXX XXXXXXX). So XXXX XXXXXX XXX XXXX XX XXXXXXX more matter in it, the atom XXXXXX is XXXXXXX smaller XXXXX XXX more XXXXXXX XXXXX.
When XXXXXXX XXXX charges, atoms can XXX XXXXXXX. In XXXX case, all XX the XXXXX have XXX same XXXXXX XX totalelectrons. Look on the table and XXXX spaces XXXXXXXXX XX XXX charge. (They all have XXX XXXX number XX electrons as XX ).
XXXX XXX size XXXXXXX on how XXX XXXXXXX XXX XXX the atom XXXX more XXXXXXX will XX smaller XX the electrons XXX more tightly XXXXX.
Note: XXX XXXXXXXX XXXXX shows XXX sizes XXX atoms that aren't ions. XXX ions, XXXXXXXX the steps XXXXX.