Atoms get their properties from their electronic configuration, which is determined by the Aufbau Principle

The Ionization Energy Changes abruptly with change in the Shell (principle quantum number) of the outermost electron

So does the Size of the Atom

Here is what the periodic Table looks like when representing the Size of the Atomic Elements

This periodic table looks disjoint because of an attempt to collapse the table (make it smaller). It really should look like this: