Ionization energies get larger as you move to the right and "up" in the periodic table
Which element has the highest ionization energy:
Ar or Kr
Ga or As
S or Te
Atomic Radius' decrease from left to right and "up" of the periodic table (opposite of ionization energies).
Electronegativity increases from left to right of the periodic table. It also increase as you go "up" the periodic table. Same as Ionization energies. The exception to
this are the groups (families) 2A, 5A and
8A(noble gases) which are usually much lower in electronegativity than
the surrounding atoms.