Which direction on the periodic table is associated with higher ionization energy and higher electronegativity?

• A. Top right
• B. Bottom left
• C. Top left
• D. Bottom right

Answer: (A)

The direction that shows higher ionization energy and higher electronegativity is toward the top-right of the periodic table. Ionization energy is the energy needed to remove an outer electron, and electronegativity is the tendency to attract electrons in a bond. As you move across a period from left to right, nuclei gain more protons without a dramatic increase in shielding, so the outer electrons are pulled closer and held more tightly. That makes it harder to remove an electron (higher ionization energy) and makes the atom attract bonding electrons more strongly (higher electronegativity). Moving up a group reduces shielding and shrinks the atomic radius, further increasing both properties. So the top-right region has the largest ionization energies and the greatest electronegativities. Down-left directions have lower values because the atoms are larger with more shielding, and bottom-right likewise does not maximize both properties together.