Example:
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.
